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SIXTH CONFERENCE OF
THE CZECH NEUROSCIENCE SOCIETY
PRAGUE, NOVEMBER 19-20, 2007
2
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
The Sixth Conference of the Czech Neuroscience Society is organized by the Executive
Committee of the Czech Neuroscience Society together with the Institute of Experimental
Medicine, Academy of Sciences of the Czech Republic and the Center of Neuroscience.
Organizing Committee:
Eva Syková – Chairperson
Josef Syka – Chairman of the Programme Committee
Members:
Martin Bojar
Rastislav Druga
Cyril Höschl
Alexandr Chvátal
Jan Mareš
Ladislav Vyklický Jr.
Eduard Zvěřina
Conference Venue:
Congress Centre, Institute for Clinical and Experimental Medicine
Vídeňská 1958/9, 140 21, Prague 4,
Phone: 261362580, Fax 261362810, www.ikem.cz
Conference Secretariat:
Institute of Experimental Medicine ASCR
Vídeňská 1083, 142 20 Prague 4,
Phone: +420 241 062 239 (English), 241 062 230 (Czech)
Fax: +420 241 062 782
e-mail: [email protected] (English), [email protected] (Czech)
Website: http://uemweb.biomed.cas.cz/cns
Office Hours at the Registration Desk:
Monday, November 19
Tuesday, November 20
8:00 – 18:00
8:00 – 15:00
Posters
Posters should be set up between 8:30 and 9:00 on Monday (posters 1-44) or on
Tuesday (posters 45-76). The author should be present at his /her poster between
13:30 and 14:30.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
PROGRAMME
Monday, 19th November
08.30 – 09.00
09.00 – 09.20
09.20 – 10.50
10.50 – 11.10
11.10 – 12.40
12.40 – 14.30
14.30 – 16.00
16.00 – 16.20
16.20 – 17.30
Poster set-up
Opening of the Sixth Conference of the Czech Neuroscience
Society with presentation of Society awards.
Session 1
Coffee break
Session 2
Lunch and Poster Session 1
Session 3
Coffee break
Session 4
19.30
Dinner at Best Western Hotel Kampa, Všehrdova 16, Praha 1
Tuesday, 20th November
08.30 – 09.00
09.00 – 11.00
11.00 – 11.20
11.20 – 12.20
12.20 – 14.30
14.30 – 15.30
Poster set-up
Session 5
Coffee break
Session 6
Lunch and Poster Session 2
Session 7
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Monday, 19th November
9.00
Opening of the Sixth Conference of the Czech Neuroscience Society
with presentation of Society awards
E.SYKOVÁ, President of the Czech Neuroscience Society
9.20 - 10.50
Session 1
Chairs: A. Saria, J. Syka
9.20
First images: Activity patterns in the mouse visual cortex at eye opening
A. KONNERTH, Munich
9.50
Glutamate-mediated neuronal-glial transmission
A. VERKHRATSKY, Prague and Manchester
10.20
Stem cells, biomaterials, and their use for treatment of brain and spinal
cord injury
E. SYKOVÁ, Prague
10.50
Coffee Break
11.10 – 12.40
Session 2
Chairs: A. Konnerth, E. Syková
11.10
Activation of muscarinic and nicotinic acetylcholine receptors in the
nucleus accumbens core is necessary for the acquisition of drug
reinforcement
A. SARIA, Innsbruck
11.40
Two signalling pathways from the metabotropic glutamate receptor of
Purkinje neurons distinguished with flash photolysis and Ca2+ imaging
D. OGDEN, Paris and London
12.10
Temperature dependency of NMDA receptors
L. VYKLICKÝ JR., O. CAIS, M. SEDLÁČEK, I. DITTERT, M. HORÁK, Prague
12.40 – 14.30
Lunch and Poster Session 1
14.30 – 16.00
Session 3
Chairs: H. Kettenmann, L. Vyklický Jr.
14.30
What and Where in human audition: cortical organisation and plasticity
S. CLARKE, Lausanne
15.00
Aging of the auditory system
J. SYKA, Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
15.20
Electrophysiological approach to evaluation of CNS ageing
M. KUBA, J. KREMLÁČEK, Z. KUBOVÁ, J. LANGROVÁ, J. SZANYI, F. VÍT,
Hradec Králové
15.40
Laterality, cortical functions asymmetry, cerebellar dominance and hair
whorl
J. TICHÝ, J. BĚLÁČEK, Prague
16.00
Coffee break
16.20 – 17.30
Session 4
5
Chairs: S. Clarke, A. Verkhratsky
16.20
Microglia in health and disease
H. KETTENMANN, Berlin
16.50
Bilateral changes of SDF-1 and its receptor CXCR4 in the dorsal root
ganglia of chronic constriction injury and spinal nerve ligation models
of neuropathic pain
P. DUBOVÝ, I. KLUSÁKOVÁ, I. SVÍŽENSKÁ, R. JANČÁLEK, Brno
17.10
The role of peripheral and central TRPV1 receptors in pain transmission
and modulation
J. PALEČEK, E. POSPÍŠILOVÁ, D. ŠPICAROVÁ, Prague
19.30
Dinner at Best Western Hotel Kampa, Všehrdova 16, Praha 1
Tuesday, 20th November
9.00 – 11.00
Session 5
Chairs: D. Ogden, J. Paleček
9.00
Molecular Properties of P2X Receptor-Channels
S.S. STOJILKOVIC, Bethesda
9.30
Interactions between the 5-HT2a and mμ opioid receptors: implications
for tolerance and responsivness to morphine
G. MILLIGAN, Edinburgh
10.00
Comparison of agonist-stimulated G-protein activity in brain cortex
membranes isolated from control and morphine-treated rats
P. SVOBODA, J. STOHR, L. BOUŘOVÁ, V. RUDAJEV, V. LISÝ, K.
KLUČKOVÁ, J. NOVOTNÝ, Prague
10.20
Opposite effects of rapacuronium on acetylcholine binding and
signaling at muscarinic acetylcholine receptors
J. JAKUBÍK, V. DOLEŽAL, Prague
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
10.40
Is nonquantal neurotransmitter release always nonvesicular?
F. VYSKOČIL, Prague
11.00
Coffee break
11.20 – 12.20
Session 6
Chairs: G. Milligan, A. Chvátal
11.20
Clinical application of BOLD fMRI
J. VYMAZAL, R.JECH, Prague
11.40
In vivo metabolomics and genetics in patients with creatine deficiency
M. HÁJEK, M. DEZORTOVÁ, V. MALINOVÁ, M. JIRSA, Prague
12.00
New method for non-invasive measurement of head position
R. ČERNÝ, M. BOJAR, J. HOZMAN, D. ŠTURM, Prague
12.20 – 14.30
Lunch and Poster Session 2
14.30 – 15.30
Session 7
Chairs: S.S. Stojilkovic, P. Dubový
14.30
Effects of LiCl/PILOCARPINE-induced status epilepticus on rat brain
benzodiazepine receptor binding: regional and ontogenetic study
H. KUBOVÁ, L. SUCHOMELOVÁ, L. ROCHA, Prague
14.50
Neuronal degeneration induced by status epilepticus in the nucleus
accumbens and in the olfactory tubercle of immature rats
R. DRUGA, H. KUBOVÁ, P. MAREŠ, Prague
15.10
Effects of two GABA-B receptor agonists on cortical epileptic
afterdischarges in immature rats are not identical
P. MAREŠ, N. TABASHIDZE, Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
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POSTERS
Monday, 19th November, Poster Session 1
1. Possible Role of the Ca2+/Calmodulin Dependent Kinase II Phosphorylation
Site T704 in Acute Desensitization of the Vanilloid Receptor TRPV1
J. BENEDIKT, K. TOUŠOVÁ, K. SUŠÁNKOVÁ, A. SAMAD, L. VYKLICKÝ,
J. TEISINGER, V. VLACHOVÁ, Prague
2. PKA dependent effect of pregnenolone sulfate on NMDA receptors
expressed in hippocampal neurons
M. PETROVIC, H. CHODOUNSKÁ, M. SEDLÁČEK, L. VYKLICKÝ JR., Prague
3. The changes in phosphatidyl inositol 4,5 bisphosphate (PIP2) levels related
to the TRPA1 channel activity
A. SAMAD, J. BENEDIKT, L. VYKLICKÝ, J. TEISINGER, V. VLACHOVA, Prague
4. Fluorometry of thermosensitive TRP channels: more than complementary
method for understanding structure-function relations
F. TOUŠKA, J. KRŮŠEK, K. SUŠÁNKOVÁ, V. VLACHOVÁ, Prague
5. TRPV1 endogenous agonist N-oleoyldopamine (OLDA) modulates
nociceptive synaptic transmission in the spinal cord
D. ŠPICAROVÁ, J. PALEČEK, Prague
6. In vitro calcium imaging of spinal cord dorsal horn neurons
D. SOJKA, J. PALEČEK, Prague
7. Chronic constriction injury in weanling rats
Š. VACULÍN, M. FRANĚK, R. ROKYTA, Prague
8. Quantitative changes of IL-6 protein are presented not only in the lumbal, but
also in the cervical DRG following unilateral sciatic nerve injury
Z. VESELKOVÁ, P. DUBOVÝ, I. SVÍŽENSKÁ, I. KLUSÁKOVÁ, Brno
9. Engraftment of donor cells in CNS depends on proper timing of host
irradiation after preconditioning with cyclophosphamide
P. JIROUTEK, L. ŠEFC, Prague
10. Electrophysiological characterization of D6/GFP-neural stem/progenitor cells
during in vitro differentiation and after transplantation into the injured rat
brain
M. ANDĚROVÁ, I. PRAJEROVÁ, P. HONSA, O. MACHOŇ, A. CHVÁTAL, Prague
11. Differentiation of neural stem cells expressing Sonic Hedgehog and Wnt-7a
I. PRAJEROVÁ, P. HONSA, M. ANDĚROVÁ, A. CHVÁTAL, Prague
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
12. Ischemia-induced Volume Changes in Astrocytes: The Role of Chloride
Movement
J. BENEŠOVÁ, M. ANDĚROVÁ, M. HOCK, O. BUTENKO, I. PRAJEROVÁ,
A. CHVÁTAL, Prague
13. Changes in the expression of K+ and Na+ channels in astrocytes and NG2
glia after ischemia in vivo
H. NEPRAŠOVÁ, M. ANDĚROVÁ, J. BENEŠOVÁ, O. BUTENKO, A. CHVÁTAL,
Prague
14. Human embryonic stem cells (CCTL14) differentiate into a neuronal
phenotype
N. KOZUBENKO, M. KAPCALOVÁ, M. ANDĚROVÁ, O. BUTENKO, A. HAMPL,
P. JENDELOVÁ, E. SYKOVÁ, Prague
15. Properties and growth of human bone marrow mesenchymal stem cells in
different media
K. TURNOVCOVÁ, K. RŮŽIČKOVÁ, P. JENDELOVÁ, E. SYKOVÁ, Prague
16. Co-transplantation of olfactory ensheathing cells and mesenchymal stem
cells improves hindlimb performance after spinal cord injury, but does not
show synergistic benefits
T. AMEMORI, K. RŮŽIČKOVÁ, G.D. ARBOLEDA TORO, P. JENDELOVÁ,
E. SYKOVÁ, Prague
17. Mobilization of bone marrow cells induced by G-CSF and FLT3 ligand
K. LIKAVČANOVÁ, L. URDZIKOVÁ, J. ŠEDÝ, P. JENDELOVÁ, E. SYKOVÁ,
Prague
18. Experimental spinal cord injury reconstruction using hydrolytically
degradable hydrogels
A. HEJČL, P. LESNÝ, J. ŠEDÝ, M. PŘÁDNÝ, J. MICHÁLEK, P. JENDELOVÁ,
E. SYKOVÁ, Prague
19. Growth of rat mesenchymal stem cells on layers of nonwoven nanofibers
from different biocompatible polymers
M. KAPCALOVÁ, P. LESNÝ, P. JENDELOVÁ, L. MARTINOVÁ, E. SYKOVÁ,
Prague
20. Nonwoven nanofiber materials as three-dimensional tissue constructs in
spinal cord injury
P. LESNÝ, O. JIRSÁK, P. JENDELOVÁ, J. MICHÁLEK, M. PŘÁDNÝ,
L. MARTINOVÁ, E. SYKOVÁ, Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
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21. Development of neurogenic pulmonary edema in spinal cord injured rats –
the role of isoflurane anesthesia
J. ŠEDÝ, L. URDZIKOVÁ, K. LIKAVČANOVÁ, A. HEJČL, M. BURIAN,
P. JENDELOVÁ, J. ZICHA, J. KUNEŠ, E. SYKOVÁ, Prague
22. Extracellular space diffusion parameters in focal cortical dysplasia
A. HOMOLA, L. VARGOVÁ, J. ZÁMEČNÍK, P. KRŠEK, P. MARUSIČ, E. SYKOVÁ,
Prague
23. Diffusion parameters in the rat cerebral cortex during pilocarpine-induced
status epilepticus
L. DMYTRENKO, K. ŠLAIS, I. VOŘÍŠEK, E. SYKOVÁ, Prague
24. Time course of water diffusivity in the rat brain after global ischemia
I. VOŘÍŠEK, H. NEPRAŠOVÁ, M. ANDĚROVÁ, D. JIRÁK, M. HÁJEK,
E. SYKOVÁ, Prague
25. Calbindin and S100 protein expression in the developing inner ear of mice
D. BUCKIOVÁ, J. SYKA, Prague
26. Changes in GAD levels in the central auditory system of two rat strains with
aging
J. BURIANOVÁ, L. OUDA, O. PROFANT, J. SYKA, Prague
27. Aging influences parvalbumin expression in the central auditory system of
two rat strains
L. OUDA, R. DRUGA, J. SYKA, Prague
28. Age-specific impairment of hearing function in the rat
N. RYBALKO, D. ŠUTA, J. PELÁNOVÁ, S. HAMSOVÁ, J. SYKA, Prague
29. Mapping the auditory cortex in the rat by the expression of cytoskeletal
neurofilament protein
R. DRUGA, J. SYKA, Prague
30. Functional and electrical membrane properties of neurons in the auditory
cortex in rats
O. PROFANT, K. LOMAKINA, R. TUREČEK, J. SYKA, Prague
31. Effect of noise exposure on the amplitudes of auditory evoked responses in
rats
J. GRÉCOVÁ, J. POPELÁŘ, J. SYKA, Prague
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
32. Spontaneous otoacoustic emissions in children and adolescents - effect of
cisplatin treatment
J. PELÁNOVÁ, D. SUMERAUER, M. ZÁPOTOCKÝ, M. JILEK, D. GROH,
Z. KABELKA, J. STARÝ, J. SYKA, Prague
33. Hearing thresholds in the extended frequency range as a function of age and
sex
M. JILEK, J. SYKA, Prague
34. Auditory cochlea-threedimensional MRI of the left and right cochleovestibular organ
J. TICHÝ, T. VITÁK, O. DLOUHÁ, Prague
35. Adaptation of the olfactory receptor neuron of a moth to the natural
pheromone signal
L. KOŠŤÁL, P. LÁNSKÝ, J.-P. ROSPARS, Prague
36. Optimal odor intensity in simple olfactory neuronal models
O. POKORA, P. LÁNSKÝ, Prague
37. Rats do not learn to avoid a cued moving region in a stationary environment
but they learn to avoid the cued region if it is stationary in a moving
environment
K. BLAHNA, B. OSECKÁ, V. MAŇÁSKOVÁ, D. KLEMENT, Prague
38. Are inertial stimuli and/or motor skills sufficient for successful navigation of
rats in the AAPA task (moving world)?
I. FAJNEROVÁ, J. KENNEY, D. KLEMENT, Prague
39. Strategies used by rats during navigation toward a visible moving target
D. KLEMENT, K. BLAHNA, Prague
40. Role of posterior parietal cortex of the rat in two tasks involving dynamic
environment
J. SVOBODA, P. TELENSKÝ, J. BUREŠ, Prague
41. Study of animal cognitive functions using an active allothetic place
avoidance task: assets, problems, questions
A. STUCHLÍK, K. VALEŠ, Prague
42. All subtypes of mild cognitive impairment are impaired in episodic-like
memory
K. VLČEK, J. LACZO, O. VAJNEROVÁ, M. ORT, M. VYHNÁLEK, J. HORT,
Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
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43. The effect of enforced physical activity and cerebellar transplantation on
spatial learning in Lurcher mutant mice
J. CENDELÍN, I. KORELUSOVÁ, F. VOŽEH, Pilsen
44. Retrospective longitudinal study of titres of specific antibodies to β tubulin
class III in patients with MS and depression treated by glatimeracetate and
SSRI
Š. CIHELKOVÁ, M. MINÁRIKOVÁ, M. HLADÍKOVÁ, D. ŠKODA, P. JINOCH,
M. BOJAR, Prague
Tuesday, 20th November, Poster Session 2
45. Regulation of RGS3 function by 14-3-3 protein
E. BOUŘA, T. OBŠIL, Prague
46. Does 14-3-3 Protein Affect Conformation of FoxO4 DNA-Binding Domain?
J. ŠILHÁN, E. BOUŘA, P. VÁCHA, P. HERMAN, J. VEČER, T. OBŠIL, Prague
47. Determinants of calmodulin binding site on the C-tail of TRPC6 channel
E. FRIEDLOVÁ, L. GRYCOVÁ, Z. LÁNSKÝ, M. ŠULC, J. TEISINGER, Prague
48. ATP binding studies on the C - termimus TRPV1
L. GRYČOVÁ, Z. LÁNSKÝ, E. FRIEDLOVÁ, M. KUBALA, J. TEISINGER, Prague
49. Possible involvement of ryanodine receptor-controlled calcium release in
sensitization of GnRH-stimulated IP3 receptor in melatonin-sensitive
neonatal gonadotrophs of the rat
A. BALÍK, I. SVOBODOVÁ, H. ZEMKOVÁ, Prague
50. Identification of Transmembrane Residues Contributing to Channel Gating
and Interaction with Ivermectin at Rat Purinergic P2X4 Receptor
H. ZEMKOVÁ, I. JELÍNKOVÁ, V. VÁVRA, M. JINDŘICHOVÁ, T. OBŠIL,
H.W. ZEMKOVÁ, S.S. STOJILKOVIC, Prague and Bethesda
51. Disruption of the plasma membrane structure by depletion of cholesterol
impairs effectiveness of TRH receptor-mediated signal transduction via
Gq/11-alpha protein
P. OSTAŠOV, J. NOVOTNÝ, L. BOUŘOVÁ, L. HEJNOVÁ, P. SVOBODA, Prague
52. Calcium responses to thyrotropin-releasing hormone and angiotensin II. The
role of plasma membrane integrity and effect of G11-alpha protein
overexpression on homologous and heterologous desensitization
J. NOVOTNÝ, P. OSTAŠOV, J. KRUŠEK, D. DURCHÁNKOVÁ, P. SVOBODA,
Prague
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
53. Delayed effects of xanomeline on evoked ACh release from rat brain slices
E. MACHOVÁ, J. JAKUBÍK, E.E. EL-FAKAHANY, V. DOLEŽAL, Prague
54. Cholesterol differentially influences G-protein signalling activated by the
muscarinic M2 receptor
P. MICHAL, E.E. EL-FAKAHANY, V. DOLEŽAL, Prague
55. Looking for fluorescent probes for allosteric binding sites at muscarinic
receptores: Unusual, but not exclusive, mechanism of interactions of tacrine
at muscarinic receptors
J. PROŠKA, M. DVOŘÁK, Prague
56. M1 receptors participate in the nonquantal acetylcholine regulation via
feedback NO action
AI MALOMOUZH, MR MUKHTAROV, EE NIKOLSKY, F. VYSKOČIL, Prague
57. Photoperiodic entrainment of the circadian molecular clock in the mice SCN
S. SOSNIYENKO, R. HUT, K. MATĚJU, M. SLÁDEK, H. ILLNEROVÁ,
A. SUMOVÁ, Prague
58. Subunit composition of hippocampal NMDA receptor in heuristic (animal)
model of schizophrenia
F. ŠŤASTNÝ, J. KLASCHKA, I. KOZMÍKOVÁ, H. TEJKALOVÁ, M. VRAJOVÁ,
Praha
59. Acute and subchronic administration of quinolinic acid and psychotic-like
behaviour in neurodevelopmental model of schizophrenia
H. TEJKALOVÁ, J. KLASCHKA, F. ŠŤASTNÝ, Prague
60. Protein expression of NMDA-NR1 subunit and acoustic startle in genetic
(animal) model of schizophrenia
M. VRAJOVÁ, H. TEJKALOVÁ, J. KLASCHKA, F. ŠŤASTNÝ, Prague
61. Lateralization of 17beta-hydroxysteroid dehydrogenase type 10 in
hippocampi of demented and psychotic patients
Z. KRIŠTOFIKOVÁ, D. ŘÍPOVÁ, P. HOVORKOVÁ, A. HOŘÍNEK, E. MAJER,
J. ŘÍČNÝ, Prague
62. Absorption of high-frequency electromagnetic radiation by the mouse brain;
theoretical model and real experiment
J. BARCAL, V. ŽALUD, F. VOŽEH, J. VRBA, Prague
63. Calretinin-containing neurons in normal and epileptic human temporal
neocortex
F. BAŘINKA, R. DRUGA, J. ZÁMEČNÍK, Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
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64. Changes in the permeability of blood brain barrier: Cortical photothrombosis
and epileptic seizure induced by flurothyl inhalation
D. KRÝSL, L. TŮMA, J. POKORNÝ, J. MAREŠ, Prague
65. Preconditioning effect of normobaric intermittent hypoxia on behavioral
consequences of chemically induced seizures in rats
K. DEYKUN, M. POMETLOVÁ, J. MAREŠ, Prague
66. The Effect of ET-1 on the Excitability of the Rat Cortical and Hippocampal
Slices in Vitro
R. KONOPKOVÁ, I. VILAGI, S. BORBELY, H. KUBOVÁ, J. OTÁHAL, Prague
67. Alteration of regulation of the regional cerebral blood flow in chronic
epileptic rats
J. OTÁHAL, G. TSENOV, P. MRÁZOVÁ, H. KUBOVÁ, Prague
68. Effects of metabotropic glutamate receptor 5 antagonist MPEP on learning in
developing rats
A. MIKULECKÁ, P. MAREŠ, Prague
69. Does paraldehyde treatment participate in short-term effects of status
epilepticus in immature rats?
G. TSENOV, H. KUBOVÁ, P. MAREŠ, Prague
70. Software for synchronous electrophysiologic and image recordings and high
level mathematical analysis
E. KRAJČOVIČOVÁ, M. MARTÍNKOVÁ, R. KONOPKOVÁ, M. FEJTOVÁ,
J. OTÁHAL, Prague
71. Effect of methamphetamine exposure and postnatal care on sensorimotor
development of rat pups
L. HRUBÁ, B. SCHUTOVÁ, M. POMETLOVÁ, R. ŠLAMBEROVÁ, Prague
72. Effect of methamphetamine on social and locomotion behaviors of adult
male rats
B. SCHUTOVÁ, L. HRUBÁ, M. POMETLOVÁ, K. DEYKUN, R. ŠLAMBEROVÁ,
Prague
73. Effect of acute methamphetamine administration on seizures in adult male
and female rats prenatally exposed to the same drug
R. ŠLAMBEROVÁ, B. SCHUTOVÁ, L. HRUBÁ, K. BERNÁŠKOVÁ,
I. MATĚJOVSKÁ, R. ROKYTA, Prague
74. Analgesic effect of acute methamphetamine in prenatally stressed and
methamphetamine-treated rats
A. YAMAMOTOVÁ, R. ŠLAMBEROVÁ, R. ROKYTA, Prague
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
75. Grooming induced by intraperitoneal application of malanotan II, a dirivative
of α-MSH
S. HYNIE, M. FLEGEL, V. KLENEROVÁ, Prague
76. Carbetocin improves deterioration of stress-induced behavior in the openfield device
V. KLENEROVÁ, M. FLEGEL, P. ŠÍDA, S. HYNIE, Prague
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
ABSTRACTS
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
LECTURES
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
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Stem cells and biomaterials in treatment of brain and
spinal cord injury
E. SYKOVÁ
Institute of Experimental Medicine ASCR and Department of Neuroscience, Charles
University, Second Medical Faculty
In the last decade, neurotransplantation research has focused on the potential
of embryonic and adult stem cells to replace damaged cell populations and to produce
missing transmitters, neuroactive substances and growth factors. Neural as well as nonneural stem cell therapy might overcome the low regenerative capacity of the human
CNS. Embryonic stem cells (ESCs) and bone marrow stromal cells (MSCs) are
pluripotent progenitor cells that have the capacity to migrate towards lesions and induce
or facilitate site-dependent differentiation in response to environmental signals. The
behavior of rat fetal cells, mouse ESCs, rat and human MSCs and olfactory glia (OEGs)
labelled with superparamagnetic iron-oxide nanoparticles and grafted to injured rat brain
or spinal cord is studied to elucidate whether these cells are capable of survival, do not
produce tumors, differentiate into neurons and astrocytes, prevent scar formation,
promote neurogenesis and enhance regeneration. Magnetic resonance imaging (MRI)
provides a noninvasive method to study the fate of transplanted cells in vivo. Rat or
human ESCs, MSCs or OEGs can be labeled with various types of iron-oxide
nanoparticles (Neurodegen. Dis. 3:62-67, 2006) and human CD34+ cells can also be
labeled with magnetic MicroBeads (Miltenyi). In animals with a cortical or spinal cord
lesion, cells were grafted intracerebrally, contralaterally to a cortical photochemical
lesion, or injected intravenously. During the first two weeks post-transplantation,
transplanted cells migrated to the lesion. Labeled MSCs, ESCs and CD34+ cells were
visible in the lesion on MR images as a hypointensive signal, persisting for more than 2
months. Various biocompatible hydrogels (degradable and nondegradable), including
those based on non-woven nanofibres, have been developed for bridging tissue defects
and for use as 3D stem cell carriers (J. Mat. Sci. Mat. Med. 17:829-833, 2006). We also
used nanofibre constructs seeded with MSCs or OEGs labeled with iron-oxide
nanoparticles to bridge a spinal cord lesion. Our studies demonstrate that scaffolds
seeded with adult as well as with embryonic stem cells can bridge a lesion site in the
brain as well as in the spinal cord. Autologous BMC implantation has been used in a
Phase I/II clinical trial in patients with SCI (n=30). The implantation was safe, and partial
improvement was seen in patients who received BMC in the first month after injury (Cell
Transplantation, 15:675-687, 2006). We conclude that adult stem cells derived from
bone marrow are promising candidates for spinal cord lesion repair.
Supported by: MSMT CR 1M0538, IGA MZ NR/8339-3 and GACR 309/06/1246,
IGA MZ 1A8697-5.
18
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Activation of muscarinic and nicotinic acetylcholine
receptors in the nucleus accumbens core is
necessary for the acquisition of drug reinforcement
A. SARIA, J.A. CRESPO, K. STURM, G. ZERNIG
Experimental Psychiatry Unit, Department of Psychiatry, Medical University Innsbruck,
A-6020 Innsbruck, Austria
Neurotransmitter release in the nucleus accumbens core (NACore) during the
acquisition of remifentanil or cocaine reinforcement was determined in an operant
runway procedure by simultaneous tandem mass spectrometric analysis of dopamine,
acetylcholine, and remifentanil or cocaine itself. Run times for remifentanil or cocaine
continually decreased over the five consecutive runs of the experiment. Intra-NACore
dopamine, acetylcholine, and drug peaked with each intravenous remifentanil or
cocaine self-administration and decreased to pre-run baseline with half-lives of_10 min.
As expected, remifentanil or cocaine peaks did not vary between the five runs.
Surprisingly, however, drug-contingent dopamine peaks also did not change over the
five runs, whereas acetylcholine peaks did. Thus, the acquisition of drug reinforcement
was paralleled by a continuous increase in acetylcholine overflow in the NACore,
whereas the overflow of dopamine, the expected prime neurotransmitter candidate for
conditioning in drug reinforcement, did not increase. Local intra-accumbens
administration by reverse microdialysis of either atropine or mecamylamine completely
and reversibly blocked the acquisition of remifentanil reinforcement. Our findings
suggest that activation of muscarinic and nicotinic acetylcholine receptors in the
NACore by acetylcholine volume transmission is necessary during the acquisition phase
of drug reinforcement conditioning.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
19
Two signalling pathways from the metabotropic
glutamate receptor of Purkinje neurons distinguished
with flash photolysis and Ca2+imaging
D. OGDEN
Laboratoire Physiologie Cerebrale, Universite Rene Descartes Paris 5 and National
Institute for Medical Research, London.
The type 1 metabotropic receptors at parallel fibre synapses of Purkinje neurons are
coupled by Gq protein to two mechanisms of Ca2+elevation in the dendrites. Following
burst stimulation of parallel fibres or photorelease of L-glutamate an early Ca2+ release
from stores mediated by phospholipase C is precisely timed at 100 ms following
stimulation, generates a brief outward current, and requires prior spiking in the Purkinje
neuron. This is followed by a slower Ca2+ influx during the PF slow excitatory PSC
which is mediated by Ca2+ permeable cation channels independently of Ca2+release,
PLC and Purkinje neuron activity. The kinetics, pharmacological characteristics and
distribution of the two signalling paths will be described.
20
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Temperature dependency of NMDA receptors
L. VYKLICKÝ JR., O. CAIS, M. SEDLÁČEK, I. DITTERT, M. HORÁK
Department of Cellular Neuroscience, Institute of Physiology Academy of Sciences of
the Czech Republic, Prague, CZECH REPUBLIC.
NMDA receptors are highly expressed in the CNS, mediate the slow
component of excitatory transmission and play key roles in synaptic plasticity and
excitotoxicity. We have used patch clamp technique to examine temperature sensitivity
of recombinant and native NMDA receptors. Temperature dependency of the amplitude
of NR1/NR2B receptor responses was bell-shaped with maximum at ~35°C. Responses
normalized with respect to the amplitude of the single channel currents were only little
temperature sensitive at 25-35°C, however, were reversibly diminished at 45°C. Rate
constants were assessed by fitting 6-state kinetic scheme to the time courses of
macroscopic currents induced by rapid glutamate (1 mM) application at 25–45°C.
Arrhenius transformation of the rate constants characterizing NMDA receptor activity
indicate that the most temperature sensitive were the rate constants of desensitization
(Q10 = 10.3), resensitization (Q10 = 4.6) and unbinding (Q10 = 3.6). Other rate
constants and the amplitude of single channel currents were less temperature sensitive.
Deactivation of responses mediated by NR1/NR2B receptors after a brief application of
glutamate was best fit by a double exponential function with mean time constants:
temperature coefficients (τ fast: Q10 = 3.7) and (τ slow: Q10 = 2.7). In contrast, time
constants characterizing the deactivation of NMDA receptor mediated EPSCs recorded
from pyramidal neurons of the rat cortex were only weakly temperature sensitive (τ fast:
Q10 = 1.7) and (τ slow: Q10 = 1.8). The amplitude of NMDA EPSCs was diminished in
the presence of ifenprodil. Both the ifenprodil-sensitive and ifenprodil-resistant decay
time constants exhibited low temperature sensitivity. These data suggest that NMDA
receptor desensitization may affect the time course of receptor deactivation as well as
the amplitude of responses. In addition, the data indicate an existence of endogenous
factors affecting temperature sensitivity of native NMDA receptors.
Supported by GA CR (309/07/0271), AV0Z 50110509, 1M0002375201, EC and LC554
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
21
What and Where in human audition: cortical
organisation and plasticity
S. CLARKE
Service de Neuropsychologie et de Neuroréhabilitation, CHUV, 1011 Lausanne,
Switzerland
Several lines of evidence indicate that sound recognition and sound
localisation depend on two distinct, anatomically partially segregated processing
streams, often referred to as the auditory What and Where streams:
The supratemporal plane contains several histologically identified non-primary auditory
areas, some of which are specialised in sound recognition and others in sound
localisation (1, 2).
The functionally defined What and Where streams are also present on the convexity of
either hemisphere (3, 4). Hemispheric lesions centred on one or the other stream are
associated with the corresponding deficits (5). Auditory processing within these streams
is highly plastic, as demonstrated at several levels:
The representation of auditory objects differs between object categories (living vs manmade) as soon as 100 ms post-stimulus onset. Plasticity in auditory object
representations, as indexed by repetition suppression, takes place within the next 100
ms and modulates distinct brain areas from the initial categorization of sounds (6, 7).
Cortical auditory representations of space are dynamic and subject to rapid
reorganisation. Plasticity induced by a 40 minute auditory spatial discrimination training
lasts for ca 6 h, is specific for trained locations and goes beyond strengthening the
representation of the trained locations (8).
Unilateral hemispheric lesions cause major changes in the processing within
the What and Where streams in the contralateral, intact hemisphere, involving the loss
of parallel processing within the streams (9).
Thus, the auditory What and Where networks adapt at short- and long-term to
functional requirements as different as the recognition of a previously heard stimulus,
the increase in discrimination ability and postlesional reorganisation.
For further reading from our work:
1. Rivier, F., S. Clarke Neuroimage, 6 (1997) 288-304
2. Viceic D, Fornari E, Thiran JP, Maeder PP, Meuli R, Adriani M, Clarke S Neuroreport, 16 (2006)
1659-1662
3. Maeder P, Meuli RA, Adriani M, Bellmann A, Fornari E, Thiran JP, Pittet A., Clarke S.
Neuroimage, 14 (2001) 802-816
4. De Santis L, Clarke S, Murray MM. Cer Cortex, 17 (2006) 9-17
5. Clarke S., Bellmann Thiran A., Maeder P., Adriani M:, Vernet O., Regli L., Cuisenaire O.,
Thiran J.-P Exp Brain Res 147 (2002) 8-15
6. Murray MM, Camen C, Gonzalez Andino SL, Bovet P, Clarke S. J Neurosci 26 (2006) 1293-302.
7. Murray MM, Camen C, Spierer L, Clarke S Neuroimage, (2007) in press
8. Spierer L, Tardif E, Sperdin H, Murray MM, Clarke S J Neurosci 2: (2007) 5474-83
9. Adriani M., A Bellmann, R. Meuli, E. Fornari, R. Frischknecht, C. Bindschaedler, F. Rivier, J.-P.
Thiran, P. Maeder, S. Clarke Neuroimage, 20 (2003) S66-S74
22
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Aging of the auditory system
J. SYKA
Institute of Experimental Medicine, Academy of Sciences of the Czech Republic,
Prague
All mammalian species, including man, suffer from age-related hearing loss or
presbycusis. Presbycusis affects 40% of the human population over 75 years of age.
Typically, hearing in high frequencies deteriorates especially in a noisy background
conditions. The most pronounced aging-associated pathological changes appear in the
peripheral part of the auditory system; they are, however, accompanied by pathological
processes occurring in the central auditory system. The first signs of deterioration occur
in presbycusis in the cochlear outer hair cells, as detected by the recording of otoacoustic emissions. Hearing thresholds evaluated either by subjective audiometry or
objectively by evoked potentials show a combination of peripheral and central defects in
auditory function. Deteriorated temporal resolution is demonstrated by increased gap
detection thresholds.
A question arises to what extent are in presbycusis involved genetic factors. A
suitable model for the study of presbycusis is rodents, such as the mouse or rat,
particularly because of their short life-span. Among mouse strains, the most frequently
used is the C57BL/6J; rapid progress of presbycusis is also evident in Fischer 344 (F
344) rats. The fast deterioration of hearing thresholds is, in F 344 rats, accompanied by
the fast disappearance of otoacoustic emissions. The reasons for this process are
pathological changes in the function of fibrocytes in the spiral ligament and in cells of
the stria vascularis. Also, changes in the neurochemistry of the central auditory system
accompany aging in F 344 rats. In the auditory cortex, the number of parvalbuminpositive neurons significantly decreases and calretinin immuno-positive neurons
become more densely stained and the cross-sectional area of their somas increases. A
possible means of preventing the start of presbycusis was recently demonstrated in C
57BL/6J mice by treating young animals with atorvastatin or by using caloric restriction.
Supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 8113-4 and LC 554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
23
Electrophysiological approach to evaluation of CNS
ageing
M. KUBA, J. KREMLÁČEK, Z. KUBOVÁ, J. LANGROVÁ, J. SZANYI, F. VÍT
Electrophysiological lab, Dept. of Pathophysiology, Charles Univ. - Faculty of Medicine
in Hradec Králové, Czech Republic
Methods for an objective evaluation of CNS ageing are very limited and
boundaries between non-pathological (biological) brain ageing and age-associated
pathologies (e. g. dementias) are unclear. Considering the relationship between
biological ageing of the brain and cognitive ageing, we tried to compare the ageing
effect on three different levels of visual information processing with the use of three
types of visual evoked potentials (VEPs).
In 133 healthy volunteers at age of 19 - 83 years (38 ± 17 years) we
examined reactions of the primary visual cortex (to pattern-reversal stimuli), responses
of extrastriate areas to motion-onset and P300 wave in visual cognitive task (recognition
of digits and letters).
The most distinct change of visual evoked potentials parameters (VEPs) was
a prolongation of P300 latency representing highly significant delay of cognitive
processes toward elderly (2 ms/1 year of age, r = 0.71), which is more expressed in
men. Decreased cognitive functions due to ageing are signalized also by reduction of
P300 amplitude (r = -.48). Motion processing (activity of the magnocellular
system/dorsal stream) seems to be more influenced by ageing (irrespective of gender)
compared to the parvocellular system/ventral stream function according to age related
changes in latencies of the motion-onset VEPs (increase of 0.5 ms/1 year) and of the
pattern-reversal VEPs (0.3 ms/1year increase. More detailed info can be found on our
Web page http://www.lfhk.cuni.cz/elf.
We believe that VEPs might contribute as an objective tool for recognition of
physiological and pathological functional changes of the ageing brain.
Supported by Ministry of Education of the Czech Republic (VZ 0021620816).
24
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Laterality, cortical functions asymmetry, cerebellar
dominance and hair whorl
J. TICHÝ, J. BĚLÁČEK1
Department of Neurology and Department of Biophysics1
1th school of Medicíne, Charles University Prague
Body asymmetry has been studied not selectively in human beengs. Julius
Verne has mentioned captains dysphoria over a lost of shell ulit with curious
contralateral whorl. Handedness has been claimed to be a privilidge of man.
Righthandness seems to be present in 90 per cent of people on this globe. Lefthanded
people have the cortical symbolic functions localized in more than in 70% in the left
hemisphere. About 4% of „pure“ righthanded people have speech centers localized in
the right hemisphere. Variability of handedness has been found in twins. Cerebellar
dominance seems to be in accordance with handedness. Clockwise hair whorl has been
found in about 85-90% of righthanded persons. About 50% lefthanded people have
counterclockwise hair whorl.
221 healthy school children 9-11 years of age have been studied by means of
Edingurgh´s questionnaire and its modification. Five tests for increased passivity
(decreased muscle tonus) on nondominant hands and legs were recorded. Cerebellar
dominance is in our study strongly related to handedness. Hair whorl has been found as
impropriate in about 15% of girls due to hair frizzle and care. Only one child from a
group of eleven lefthanded has a counterclockwise hair whorl. Crossed footness and
handedness is present in a high percentage. The puzzle of laterality is still a provoking
event. Hair whorl, namely in boys, may be used as a complementary test for the
laterality.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
25
Bilateral changes of SDF-1 and its receptor CXCR4 in
the dorsal root ganglia of chronic constriction injury
and spinal nerve ligation models of neuropathic pain
P. DUBOVÝ, I. KLUSÁKOVÁ, I. SVÍŽENSKÁ, R. JANČÁLEK
Department of Anatomy, Division of Neuroanatomy, Medical Faculty, Masaryk
University Brno, Czech Republic
There is compelling evidence indicating that hyperalgesia, allodynia and
ongoing pain associated with peripheral nerve injury are due to changes in the DRG.
Chronic constriction injury (CCI) and spinal nerve ligation (SNL) are most frequently
used experimental models of neuropathic pain based on nerve injury.
Chemokines are small chemotactic cytokines which produce their effects by
activating a family of G-protein coupled receptors. Some recent studies have shown that
regulation of chemokines is one of the mechanisms underlying the development and
maintenance of neuropathic pain. The biological activity of stromal cell-derived factor
(SDF1) is signaled through the chemokine receptor CXCR4 which is unique among
chemokine receptors, having only one known ligand. The role of SDF1/CXCR4 in the
peripheral nervous system is implied by their early expression in neural crest
cells/derivatives as well as in the dorsal root ganglia (DRG). The goal of our
experiments was to compare an immunohistochemical staining for SDF-1 and CXCR4
proteins in the L4-L5 DRG of naïve rats and those operated for unilateral L4-L5 SNL
and CCI of sciatic nerve.
The naive DRG displayed a sharp immunofluorescence for SDF1 (SDF1-IF)
at the surface of neuron/satellite glial cell units. A significant decrease of SDF1-IF was
induced bilaterally in the L4-L5 DRG 3 days after both CCI and SNL. A diffuse
immunofluorescence for SDF1 was found in SGC after both types of nerve injuries for 1
and 2 weeks with a higher intensity following CCI.
CXCR4-IF was present in the small- and medium sized neurons and the
satellite glial cells (SGC) enveloping the large-sized neurons of naïve DRG. CXCR4-IF
was unchanged in the small- and medium sized neurons in the DRG from operated rats
for all periods of survival. A significant reduced CXCR4-IF was observed in the SGC of
contralateral DRG after both types of nerve injuries, but was elevated at the surface of
large-sized neurons of ipsilateral DRG when CCI was applied. Latter pattern of staining
was not significantly developed following SNL.
Our results suggest different regulation of SDF1/CXCR4 expression in the DRG during
various periods of survival and by the type of nerve injury used in neuropathic pain
models.
Supported by GACR 309/07/0121 and MSM0021622404.
26
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
The role of peripheral and central TRPV1 receptors in
pain transmission and modulation
J. PALEČEK, E. POSPÍŠILOVÁ, D. ŠPICAROVÁ
Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic.
Transient receptor potential vanilloid (TRPV1) receptors are expressed on
both the peripheral and central branches of dorsal root ganglion neurons. The aim of
this study was to examine the role of the TRPV1 receptors in cutaneous
hypersensitivity, present after surgical tissue injury and to evaluate the effect of
intradermal and intrathecal TRPV1 antagonist and endogenous agonists treatment. Paw
withdrawal responses to mechanical stimuli of plantar skin with von Frey filaments and
to thermal stimuli with radiant heat were tested before and at several time points after
the surgery in rat plantar incision model. Magnitude of central sensitization changes was
also judged by the number of spinothalamic (STT) and postsynaptic dorsal column
(PSDC) neurons expressing c-Fos. In the control group of animals treated with vehicle,
mechanical and thermal sensitivity increased significantly following the incision. TRPV1
antagonist (SB 366791) applied intradermally slightly attenuated the development of
thermal hyperalgesia and mechanical allodynia. Intrathecal application of this TRPV1
antagonist was much more effective, it greatly reduced postoperative thermal
hyperalgesia and also attenuated mechanical allodynia. High concentration intradermal
capsaicin application reduced the number of STT and PSDC neurons expressing c-Fos
after the incision. Intrathecal application of an endogenous TRPV1 agonist Noleoyldopamine (OLDA) did not change sensitivity to peripheral thermal stimuli.
However, it potentiated the effect of intrathecal bradykinin application. These results
were further studied using patch clamp recordings from superficial dorsal horn neurones
in spinal cord slices. Our results show that intrathecal application of TRPV1 antagonist
can reduce postoperative thermal and mechanical hypersensitivity and that both
peripheral and central TRPV1 receptors play an important role in pain transmission and
modulation.
Supported by GACR 305/06/1115, AV0Z 5011922, MSMT LC 554
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
27
Molecular Properties of P2X Receptor-Channels
S.S. STOJILKOVIC1, Z.YAN1, M. TOMIC1, T. OBŠIL2, H. ZEMKOVÁ1,2
1
Section on Cellular Signaling, DNP, NICHD, National Institutes of Health, Bethesda,
USA
2
Institute of Physiology ASCR, Prague, Czech Republic
The P2X receptors (P2XRs) are a family of ATP-gated ion channels
expressed in numerous excitable and nonexcitable cells that play important roles in the
control of cellular functions such as neurotransmission, hormone secretion,
transcriptional regulation, and protein synthesis. P2XRs are homomeric or heteromeric
proteins, formed by assembly of at least three subunits, termed P2X1-P2X7. All subunits
possess intracellular N- and C-termini, two transmembrane domains and a large
extracellular ligand-binding loop. ATP binds to ectodomain, leading to a sequence of
conformational transitions between closed, open and desensitized states of channel. No
crystal structures are available for P2XRs and receptors have no obvious similarity to
other ion channels or ATP binding proteins. These factors limit progress in the
understanding of relationships between molecular structure and receptor function. To
identify regions important for binding and gating, we used homology modeling of P2XR
based on secondary structure similarities between the Lys-180-Lys-326 ectodomain
region of P2X4R and the class II aminoacyl-tRNA synthetases. The interplay between
homology modeling and site-directed mutagenesis identified several residues that could
contribute to ATP binding, including Asp-280, Lys-190, and Arg-278. Using the same
approach, we also found that Tyr-315 is the last ectodomain residue that could
contribute to the agonist binding module, and Ile-317–Ile-333 sequence could operate
as a signal transduction module, with Gly-316 serving as a flexible residue linking the
binding and transduction modules. Using ivermectin, a positive allosteric modulator of
P2X4R, we were also able to identify the critical roles of Lys-67, Lys-313, and Arg-295
residues in forming the proper three-dimensional structure of receptor. Furthermore,
alanine and cysteine scanning mutagenesis of the two transmembrane domains
combined with ivermectin treatment helped us to identify amino acid residues facing the
pore site and playing important role in gating, including Tyr-42, Gly-340 and Asp-354, as
well as residues facing lipids in the open conformation state. We also studied the
relevance of the N- and C-terminal structures on the channel activity. Experiments with
P2X2R and P2X7R revealed that both termini contribute to the control of gating. The
efficiency of bioluminescent resonance energy transfer between luciferase and
fluorescent proteins attached to the N- or C-termini of P2X2R subunits also suggested
that the extent of subunit interactions prior to ATP application could contribute to
conformational changes associated with agonist-dependent desensitization.
Supported by the Intramural Research Program of the NICHD.
28
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Comparison of agonist-stimulated G-protein activity in
brain cortex membranes isolated from control and
morphine-treated rats
P. SVOBODA, J. STOHR, L. BOUŘOVÁ, V. RUDAJEV, V. LISÝ, K. KLUČKOVÁ, J.
NOVOTNÝ
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech
Republic
Rat brain cortex was fractionated by two-step density gradient centrifugation.
Plasma membrane fraction isolated in PercollR-gradient was sub-fractionated into the
bulk of plasma membranes (BPM) containing the major part of PM markers Na, KATPase, G-protein coupled receptors, trimeric G protein α and β subunits, caveolin(s)
and adenylyl cyclases I/II and the low-density membrane compartment, LPM. Functional
activity of trimeric G protein(s) was measured in PM compartments of different density
as agonist-stimulated [32P]GTPase. All PM fractions were characterised by high level of
basal high-affinity GTPase. Baclofen (GABAB-receptor) was the only GPCR agonist
significantly increasing this activity.
Considering the high basal GTPase in PM isolated from the brain tissue, we
tried to distinguish among different [35S]GTPγS binding sites and improve the assay
conditions for detection of agonist-stimulated G-protein activity. Saturation binding
curves were measured in wide range of [35S]GTPγS concentrations in the presence or
absence of increasing concentrations of GDP. Under optimum conditions, baclofen
(GABAB-R agonist), DAMGO (DOR agonist) and DADLE (MOR agonist)-stimulated
binding represented 193±33%, 158±23% and 135±16% of the basal level, respectively.
Net-increment of agonist-stimulation was 17 ± 4, 11 ± 3 and 7 ± 3 pmol.mg-1.
These methodological improvements were used in the last step of our work for
comparison of OR-stimulated G-protein activity in PM isolated from morphine-treated
and control animals. The net-increment of DADLE (DOR)-, DAMGO (MOR)- and U23554 (KOR) stimulated [35S]GTPS binding was measured at 30 μM GDP. Our data
indicated that
there was not significant difference between the two groups. This
conclusion applied to the absolute level of agonist-stimulated component (netincrement) as well as relative proportion between agonist-stimulated and the basal level
(expressed as % of basal level of binding, 100%). The order of potency among different
agonists was: baclofen > DADLE > DAMGO > U-695 93 and was the same in PM
isolated from control and morphine-treated rats. It may be therefore concluded that the
prolonged exposure of experimental animals (Wistar rats) to morphine does not
influence the OR-mediated increase of overall G protein activity in rat cerebral cortex
when performed under experimental conditions employed in this study. This occurs
together with the marked effect of morphine on behaviour of these animals
characterised by typical drug dependence.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
29
Opposite effects of rapacuronium on acetylcholine
binding and signaling at muscarinic acetylcholine
receptors
J. JAKUBÍK AND V. DOLEŽAL
Institute of Physiology CAS, Prague, Czech Republic
One of a promising approaches to alleviate symptoms in neurodegenerative
diseases (e.g. Alzheimer disease) is to support synaptic transmission of degenerating or
damaged neurons with allosteric drugs which potentiate binding of their natural
neurotransmitter to postsynaptic receptors in a subtype-specific manner that would
enable efficient targeting of distinct functions. Our previous finding of the positive
cooperativity between allosteric modulator thiochrome and natural transmitter
acetylcholine (ACh) at muscarinic M4 receptor that displayed absolute subtype
specificity attested viability of this concept (1). In our present study of interactions
between ACh and allosteric modulator rapacuronium at muscarinic receptors we found
that rapacuronium binds to all five subtypes of muscarinic receptors (M1-M5) and
strongly diminishes both high and low affinity binding of ACh at all subtypes. In contrast
to these findings we demonstrate in functional assays that rapacuronium enhances
receptor activation, particularly at M3 receptor, during a brief period after ACh
application. We show that the binding of GTPγS to membranes and accumulation of
inositol phosphates in intact CHO cells expressing M3 receptor subtype induced by 10
μM acetylcholine are accelerated by 1 μM rapacuronium. In accordance with these
findings we show that calcium signal after 5 second stimulation by 300 nM ACh relaxes
more slowly in the presence of 1 μM rapacuronium. These results are in line with the
view that allosteric modulators not only change occupancy of agonist but also induce
conformation different from that of receptor-agonist complex. The implication of these
findings is the necessity to employ fast functional assays which much better resemble
physiological conditions than the long lasting equilibrium binding experiments, in
screening for potential allosteric enhancers of neurotransmition.
1. Lazareno et al., Mol Pharmacol 65, 257-266, 2004.
Supported by project AV0Z50110509, grants GACR305/05/0452 and LC554.
30
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Is nonquantal neurotransmitter release always
nonvesicular?
F. VYSKOČIL
Istitute of Physiology, Czech Academy of Sciences, VÝdenska 1083, 192 20 Prague,
Czechoslovakia and Department of Animal and Human Physiology, Faculty of Science,
Charles University, Prague.
There is considerable evidence for a continuous release of ACh from motor
nerve terminals associated with the activity of vesicle ACh transporter (VAChT) inserted
into the nerve membrane during exocytosis. Early experiments implied the existence of
NQR from the hyperpolarization of the muscle (the ĹH-effectĺ) at the NMJ in response to
block of nAChRs in muscles in which the AChE activity had also been blocked. Normal
AChE activity would prevent this effect but appears to allow enough ACh to reach the
muscle to activate nAChRs. This in turn appears to trigger a postsynaptic
phosphorylation cascade that involves both Ca++ and NO as second messengers. This
cascade suppresses the activity of an inward Cl - transporter and this supports the local
hyperpolarization of the muscle in the region of the NMJ, thus helping to maintain
muscle excitability. A number of factors including AChE activity and purines released
from the nerve appear to influence the magnitude of NQR and the effects resulting from
it. VAChT hypothesis indicates that NQR is a residue of the quantal release. During
synapse formation and reinervation, NQR appears earlier, by about 3 days, indicating
the nonvesicular nonquantal release. This important fact is furher discussed. While the
true physiological significance of NQR is slowly emerging, it seems that a "byproduct" of
the exocytosis causing ACh release may play a significant role in regulating
postsynaptic excitability at the NMJ. A number of factors including AChE activity and
ATP released from the nerve also influence the magnitude of NQR and the effects
resulting from it are quite substantial.
Grants RSSF,GAAVA5011411,AV025011922 and LN544.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
31
Clinical application of BOLD fMRI
J. VYMAZAL, R. JECH
Na Homolce Hospital, Prague
Blood oxygen level dependence (BOLD) contrast is a powerful tool in
functional magnetic resonance imaging (fMRI). BOLD is based on different magnetic
properties of oxyhemoglobin and deoxyhemoglobin. While oxyhemoglobin is
diamagnetic i.e. has no specific magnetic properties, deoxyhemoglobin is paramagnetic
and thus causes inhomogeneities of the local magnetic field that can be detected with a
sensitive imaging sequence. Thus, BOLD does not show directly the synaptic neuronal
activity but rather the increase in the regional cerebral blood flow (rCBF) with a relative
increase of oxyhemoglobin in activated areas. The deoxyhemoglobin effect (on T2 and
T2* relaxation), responsible for BOLD, is roughly quadratically dependent on the
external magnetic field strength.
Using various paradigms BOLD can detect different brain centers and also
relate them to various pathologies. BOLD has been widely used in neurosurgery,
neurology, psychiatry and neuroscientific research.
The resulting activated areas are displayed as statistical maps that are
displayed over the morphological images.
We present our experience with BOLD fMRI in the routine intraoperative
neurosurgical navigation especially for brain gliomas where the functional blobs are
incorporated into the 3D brain imaging. Furthermore, we present the BOLD data from
deep brain stimulation (DBS) for Parkinson´s disease, in lateralization of speech center
in epileptology and in the combination with transcranial magnetic stimulation in some
extrapyramidal disorders.
32
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
New method for non-invasive measurement of head
position
R. ČERNÝ1, M.BOJAR1, J. HOZMAN2, D. ŠTURM2
1
Charles University in Prague, 2nd Faculty of Medicine, Clinic of Neurology, Praha,
Czech Technical University in Prague
2
Faculty of Biomedical Engineering, Kladno
Background
Quantitative assessment of head alignment in space has potential importance in many
diseases of nervous system – movement disorders, neuro ophthalmology and vestibular
disorders. Surprisingly little is known about limits of natural head position in healthy
human, particularly in torsional (yaw) plane. Today, head position is evaluated by simple
assessment, by deviation from plumb line or by sophisticated or invasive techniques
(eg. magnetic search coil technique for eye-head co registration in vestibulo-ocular
reflex studies, X-ray evaluation of head posture in orthodoncy). In view of these
shortcomings, we have proposed a simple, non-invasive, but precise method of
undisturbed head position in all 3 dimensions of space.
Methods
Authors developed a simple, non-invasive method of head position measurement.
Pictures of the head with marks placed on tragus and eye outer canthus on each side
are taken simultaneously by two digital cameras aligned in space by laser beam. Angle
deviation of orbito-meatal and interorbital lines from horizontal plane and head rotation
are automatically evaluated by digital picture analysis.
As evidenced by experiments done with mechanical head model, head
position is measured with precision of 0.5 degree in all three dimensions (rotation,
flexion and inclination).
Results
We present details of measurement methodology and results from a control group
consisting of 100 healthy volunteers.
Mean values of head position in control subjects: retroflexion 21 deg, inclination to the
right 0.2 deg, and head rotation to the left 1.7 deg.
Illustrative cases of acute vestibular failure, torticollis and compensatory head posturing
in ocular muscle palsy are shown.
Conclusions
New method of non-invasive, high precision head posture measurement using digital
picture analysis is presented.
Results from a control group and clinical examples are demonstrated.
This work is supported by the Czech Ministry of Health grant No: NR8261-3/2005
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
33
Effects of LiCl/PILOCARPINE-induced status
epilepticus on rat brain benzodiazepine receptor
binding: regional and ontogenetic study
H. KUBOVÁ1, L. SUCHOMELOVÁ1, L. ROCHA2
1
Department of Developmental Epileptology. Institute of Physiology. Academy of
Sciences of the Czech Republic, Czech Republic .
2
Department of. Pharmacobiology, Center of Research and Advanced Studies. Mexico
City, Mexico.
Convulsive status epilepticus (SE) represent highly destructive and
epileptogenic brain insult. Severity of SE-induced damage as well as incidence of
epilepsy increases with age at SE onset. There is however no clear correlation between
severity of morphological damage and epileptogenesis or seizure pattern. Recent data
demonstrate that changes in receptor structures play an important role in changes of
brain excitability and development of epilepsy. The involvement of GABA receptors in
seizure development and also their role during epileptogenesis was well documented by
neurochemical, pharmacological as well as electrophysiological studies. Some studies
suggest that the role of GABA receptors in epileptogenesis can be age-related, data are
however limited. Thus, present study was designed to extend present knowledge about
SE-induced changes of GABA receptors at different levels of brain maturation.
In present study, LiCl/pilocarpine-induced status epilepticus (SE), which leads
to development of epilepsy in all adult andin a subpopulation of immature rats (Kubova
et al, EJN, 2004), was induced in P12, P25 and/or adult rats. Using in vitro
autoradiography, benzodiazepine (BDZ) receptor binding was evaluated one week
(early phase of epileptogenesis) and 3 months (chronic phase) after SE in 27 brain
structures, involved in seizure generation and spread (amygdala complex,
hippocampus, basal ganglia, thalamic nuclei and several cortical regions). The pattern
of receptor binding changes was highly related to the age at SE, interval after SE and to
the brain structure evaluated. One week after SE, enhanced BDZ binding was found in
P12 group in most of cortical areas and in both P12 and P25 groups also in the
amygdala complex and dentate gyrus. No changes of BDZ binding occurred in adults at
that time point, but three months after SE a decrease of binding was found in both adult
and P25 rats in all evaluated areas. In P12 group, a significant decrease of BZS binding
occurred only in the entorhinal cortex. The decrease of binding did not reflect neuronal
loss. Our data support hypothesis that age-related pattern of changes of receptor
properties may participate in different functional consequences of SE including
epileptogenesis and altered behavior.
Supported by a grant No 304/05/2582 and 305/03/H148 of the Grant Agency of the
Czech Republic and by CONACyT (Grant 45943-M), Mexico
34
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Neuronal degeneration induced by status epilepticus
in the nucleus accumbens and in the olfactory
tubercle of immature rats
R. DRUGA¹,², H. KUBOVÁ¹, P. MAREŠ¹
1
Developmental Epileptology, Institute of Physiology CAS, Prague, Czech Republic
Institute of Anatomy, 2nd Medical Faculty, Charles University, Prague, Czech Republic
2
The basal forebrain consists of a number of closely related nuclei and regions
with complicated architecture. Prominent among these are the nucleus accumbens septi
(NAS) and the olfactory tubercle (OT) which share morphological and chemical
characteristics with striatal regions and are considered the major component of the
ventral striatum. Nucleus accumbens is divided into ventromedial shell and dorsolateral
core compartments. Olfactory tubercle exhibits in macrosmatics laboratory animals
laminated structure. Both compartments of the nucleus accumbens and the olfactory
tubercle differ in structure and functions. In an effort to better understand the
development of neuronal damage in the striatopallidal complex after status epilepticus
(SE) neuronal degeneration was analyzed within both compartments of the NAS and in
the olfactory tubercle.
Experiments were carried out in Wistar pups 25 days old. Lithium-pilocarpine
model of SE was used. The rats survived for 4, 8, 12, 24, 48 hours and 1 week after
SE. Degenerated neurons were detected with a fluorescent stain Fluoro - Jade B (FJB).
The basal forebrain was partitioned into different nuclear groups according to Paxinos
and Watson (1997).
A small to moderate number of FJB – positive (degenerated) neurons was
found 4 - 12 hours after SE in the NAS. These neurons were distributed in the shell
compartment of the NAS. The core region contained only isolated degenerated neurons
in short intervals after SE. At survival interval 24 hours the number of degenerated
neurons in the shell subdivision of the NAS significantly increased and FJB – positive
neurons were evident in the whole extend of the nucleus. At longer survival intervals (48
h, 1 week) degenerated neurons persisted in the shell subdivision of the NAS but their
number was significantly reduced. In the ventral pallidum was negative finding. In the
OT degenerated neurons were discernible for the first time 12 h after SE and prevailed
in deeper layers.
In summary, data show that the lithium – pilocarpine model of SE resulted in
degeneration of neurons not only in the dorsal striatum but in the same survival intervals
after SE also in the nucleus accumbens and in the olfactory tubercle. In all survival
intervals degenerated neurons significantly prevailed in the shell subdivision of the NAS.
In the core subdivision of the NAS were degenerated neurons rare. Olfactory tubercle
was less damaged than shell compartment of the NAS. In the ventral pallidum was in all
survival intervals negative finding.
(Supported by Grant No. 304/07/1137 of the Grant Agency of the CR).
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
35
Effects of two GABA-B receptor agonists on cortical
epileptic afterdischarges in immature rats are not
identical
P. MAREŠ, N. TABASHIDZE
Department of Developmental Epileptology, Institute of Physiology, Academy of
Sciences of the Czech Republic, Prague, Czech Republic
RATIONALE: Baclofen, a classical GABA-B receptor agonist, was found to elicit both
anticonvulsant and proconvulsant effects. In addition, these effects change during
postnatal development. Therefore we compared the effects of baclofen with another
agonist SKF97541 to know if these actions are a general feature of GABA-B receptor
agonsts or if they are specific for baclofen.
METHODS: Epileptic afterdischarges (ADs) elicited by stimulation of sensorimotor
cortex were used as a model. To study developmental changes 12-, 18- and 25-day-old
rats were used. Animals with implanted electrodes were repeatedly stimulated with 15-s
series of 1-ms pulses at 8-Hz frequency. Intensity of stimulation current was stepwise
increased with repeated stimulations from 0.2 to 15 mA. Thresholds for four phenomena
(movements directly elicited by stimulation, epileptic ADs characterized by spike-andwave EEG rhythm, clonic seizures bound to this type of ADs and a transition into the
second, mixed type of ADs with features characteristic for ADs generated in limbic
structures) were established, intensity of motor phenomena was scored and duration of
ADs was measured.
RESULTS: Decreased intensity of motor phenomena was observed after either agonist,
i.e. they exhibited an anticonvulsant action. At the same time proconvulsant effects
were registered - decreased threshold intensities necessary for elicitation of mixed ADs,
for transition of epileptic activity into limbic structures and significant prolongation of
ADs. SKF97541 is much more potent than baclofen. Differences between actions of the
two drugs were also found. SKF97541 increased threshold intensities of stimulation
current necessary for elicitation of stimulation-bound movements, spike-and-wave type
of ADs and accompanying clonic seizures in 12- and 18-day-old rats, baclofen did not
exhibit this effect. Quantitative differences were found with all effects. They were clearly
seen in suppression of intensity of both motor phenomena (movements and clonic
seizures) was more marked with SKF97541 in 12- and 18-day-old rats than with
baclofen where this effect was only marginal.
CONCLUSIONS: Differences between the action of the two GABA-B receptor agonists
may be due to their action on different subsets of receptors but further studies are
necessary.
This study was supported by grant No. 305/05/2581 of the Grant Agency of the Czech
Republic and by a research project AV0Z 50110509.
36
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
POSTERS
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
37
Possible role of the Ca2+/calmodulin dependent kinase
II phosphorylation site T704 in acute desensitization
of the vanilloid receptor TRPV1
J. BENEDIKT, K. TOUŠOVÁ, K. SUŠÁNKOVÁ, A. SAMAD, L. VYKLICKÝ, J.
TEISINGER, V. VLACHOVÁ
Department of Cellular Neurophysiology, Institute of Physiology AS CR, Prague, Czech
Republic
Capsaicin-induced desensitization of the Transient Receptor Potential
Vanilloid receptor-1 (TRPV1) is one of the key strategies for the treatment of
neuropathic and inflammatory pain. This process is initiated by TRPV1 receptor
activation and the subsequent entry of extracellular Ca2+ through the channel into
primary afferent neurons. It is generally assumed that TRPV1 desensitization is caused
by dephosphorylation by the Ca2+/calmodulin-dependent enzyme, phosphatase 2B
(calcineurin). Of several consensus phosphorylation sites identified so far, the most
notable are two sites for Ca2+/calmodulin dependent kinase II (CaMKII) at which the
dynamic equilibrium between the phosphorylated and dephosphorylated states
presumably regulates the binding of the agonist. Using whole-cell patch-clamp
technique in HEK293T cells expressing the wild type or CaMKII phosphorylation site
mutants of TRPV1, we investigated the mechanisms of acute Ca 2+-dependent
desensitization. The nonphosphorylatable mutant S502A/T704I was capsaicininsensitive but the S502A/T704A construct retained its full function, indicating a
requirement for a specific residue at position 704. Alanine mutation at the nearby
conserved residue R701 strongly affected the heat, capsaicin and pH-evoked currents.
As this residue constitutes a stringent CaMKII consensus site but is also predicted to be
involved in the interaction with membrane phosphatidylinositol 4,5-bisphosphate (PIP2),
this data suggests that in addition to dephosphorylation, or as its result, a short Cterminal juxtamembrane segment neighbouring to the TRP box comprised of R701 and
T704 might be involved in the decelerated gating kinetics of the desensitized vanilloid
TRPV1 channel.
This work supported by the Czech Science Foundation, 305/06/0319, the Research
Project Fund of the AS CR, AV0Z50110509, and by the Ministry of Education, Youth
and Sports of the Czech Republic (1M0002375201, MSM6007665808 and LC554).
38
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
PKA dependent effect of pregnenolone sulfate on
NMDA receptors expressed in hippocampal neurons
M. PETROVIČ1, H. CHODOUNSKÁ2, M. SEDLÁČEK1, L. VYKLICKÝ JR.1
1
Institute of Physiology, AS CR, Prague, Czech Republic
Institute of Organic Chemistry and Biochemistry AS CR, Prague, Czech Republic
2
Activity of NMDA receptors can be modulated by neurosteroids, the
substances of steroid origin, having a direct nongenomic effect on neuron excitability.
We examined mechanism of action of endogenous neurosteroid
pregnenolone sulfate (PS), a positive modulator of NMDA receptor activity. Our
surprising finding was that, when PS was pre-applied to outside-out patches pulled from
hippocampal neurons grown in the culture, strong potentiating effect of PS rapidly
decayed in repetitive applications. After the first PS pre-application (300 μM), NMDA
currents were potentiated 2.11±0.11 times relative to control, but after fifth cycle, there
was practically no potentiation, 1.01±0.07, n=6. In whole-cell mode, degree of PS
potentiation was unchanged after first (3.02±0.17) and fifth application (2.94±0.06), n=6.
We also tested effect of endogenous neurosteroid pregnanolone sulfate (3α5βS), but
there was no difference in time-course of its effect on patches and whole cells.
The activity of NMDA receptors is influenced by their phosphorylation status.
We tested the effect of substances that influence the activity of neuronal kinases or
phosphatases. Addition of cyclosporine, okadaic acid, PKA catalytic subunit or BAPTA
to intracellular solution (or combination of these) produced significant changes both in
degree and the time-course of PS potentiation on NMDA receptors patches, slowing its
decay.
In whole cells, bath application of staurosporine (1h) reduced the degree of
PS pre-application to 2.02±0.12 times (n=6). Exposing the cells to NMDA (100 μM) for
30 s at the half of staurosporine application further decreased the PS potentiation to
1.68±0.05 times (n=6), but subsequent application of 8-Br-cAMP (500 μM, stimulator of
PKA) partially recovered the PS potentiation to 2.33±0.09 (n=6). The subsequent
application of phorbol 12-myristate 13-acetate (0.5 μM, stimulator of PKC) produced no
recovery 1.72±0.16 (n=6).
To specifically inhibit PKA, we bathed the cells in H-89 (50 μM) for 1 h, which
reduced PS potentiation to 2.18 ± 0.23 times (n=6). Interposing NMDA application (30 s)
further reduced the PS effect to 1.83±0.13 times (n=6). As expected, the PS
potentiation was recovered by subsequent application of 8-Br-cAMP (500 μM) to
2.58±0.13, n=6.
Our conclusion is that the potentiating effect of PS on NMDA receptors
strongly depends on their phosphorylation status and is primarily related to activity of
protein kinase A.
This work was supported by the Grant Agency of the Czech Republic (309/07/0271),
Research Project of the AS CR AV0Z 50110509 and Ministry of Education, Youth and
Sports of the Czech Republic (1M0002375201 and LC554).
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
39
The changes in phosphatidyl inositol 4.5
bisphosphate (PIP2) levels related to the TRPA1
channel activity
A. SAMAD, J. BENEDIKT, L. VYKLICKÝ, J. TEISINGER, V. VLACHOVÁ
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague 4, Institute
of Physical Biology USB, Nove Hrady, Czech Republic
The Transient Receptor Potential Ankyrin receptor-1 (TRPA1) is a
nonselective cation channel that is gated in response to pungent chemicals found, e.g.
in mustard oil, wasabi, horse radish and garlic. In primary nociceptors, this channel is
also activated by an inflammatory peptide bradykinin known to stimulate the activity of
phospholipase C which, in turn, may influence the concentration of phosphatidyl inositol
bisphosphate (PIP2). Although this membrane lipid is supposed to be required for
TRPA1 function, it is not clear to what extent it could alter the channel activity. We
examined the dynamics of PIP2 in the plasma membrane during TRPA1 activation by
using the PIP2-sensitive potassium inward rectifier ion channel (Kir2.1) coexpressed
with TRPA1 in HEK293T cells, and by measuring whole-cell inward currents elicited by
allyl isothiocyanate (AITC; 100-200 µM) in the presence of 2 mM Ca2+. We found that
intracellular dialysis with anti-PIP2 antibody or with the substances lowering PIP2 (e.g.
PIP2 scavenger poly-L-lysine, activation of endogenous PLC, and inhibitors of PIkinases required for PIP2 synthesis) significantly reduced the Kir 2.1 channel activity.
The activation of TRPA1 by AITC caused a substantial suppression of Kir2.1 currents
suggesting that the activation of TRPA1 results in potent depletion of PIP2, presumably
due to the Ca2+ influx. These results form a starting point for future studies aimed at the
unraveling of the exact molecular mechanisms underlying PIP2 modulation of TRPA1.
Supported by the Czech Science Foundation, 305/06/0319, the Research Project Fund
of the AS CR, AV0Z50110509, and by the Ministry of Education, Youth and Sports of
the Czech Republic (1M0002375201, MSM6007665808 and LC554).
40
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Fluorometry of thermosensitive TRP channels: more
than complementary method for understanding
structure-function relations
F. TOUŠKA, J. KRŮŠEK, K. SUŠÁNKOVÁ, V. VLACHOVÁ
Department of Cellular Neurophysiology, Institute of Physiology, Academy of Sciences
of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic
Thermosensitive transient receptor potential (TRP) receptors are cationselective ion channels that are gated in response to changes in ambient temperature. In
primary nociceptors, these channels are also activated by pungent irritant plant-derived
chemicals found, e.g. in red pepper, peppermint oil, mustard oil, horse radish or garlic.
Recent electrophysiological, pharmacological and biochemical studies have provided
considerable insights on how these channels contribute to thermosensation, but many
aspects of their regulation remain elusive.
In the present study, we set out to develop an approach for exploring agonistand temperature-induced activity of thermosensitive TRP channels by using
fluorescence imaging techniques, which in combination with electrophysiological
studies, can provide a sensitive and specific read-out of channelĺs gating and ion
selectivity functions. By using fura-2AM ratiometric Ca2+ imaging, we examined the
changes in [Ca2+]i induced by applications of heat or chemical stimuli in HEK293T cells
transiently transfected with either TRPV1, TRPV4, or TRPA1. We also attempted to
characterize the factors that could generally influence the multimerization of
thermosensitive channels by using the fluorescence resonance energy transfer
technique on TRPV4/TRPV6 labeled with CFP and YFP (1). Our initial results prove the
feasibility of microfluorometry to be used for future studies aimed at the unraveling of
the unique molecular mechanisms underlying thermal and chemical activation and
structure-function relationships among thermosensitive TRP channels.
(1) Hellwig et al, J Cell Sci. 2005; 118:917-28.
Supported by the Czech Science Foundation, 305/06/0319, the Research
Project Fund of the AS CR, AV0Z50110509, the Grant Agency of AS CR A100110501,
A5020406, and by the Ministry of Education, Youth and Sports of the Czech Republic
(1M0002375201 and LC554).
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
41
TRPV1 endogenous agonist N-oleoyldopamine
(OLDA) modulates nociceptive synaptic transmission
in the spinal cord
D. ŠPICAROVÁ, J. PALEČEK
Department of Functional Morphology, Institute of Physiology, Academy of Sciences of
the Czech Republic, Prague
Transient receptor potential vanilloid (TRPV1) receptors are expressed
predominantly in a subpopulation of primary sensory neurons, that convey nociceptive
information from the periphery to the spinal cord dorsal horn (DH). The TRPV1
receptors are expressed on both the peripheral and central branches of these dorsal
root ganglion neurons and can be activated, beside capsaicin, by heat, low pH and also
by recently described endogenous lipids derived from dopamine. Using patch-clamp
recordings from superficial DH neurons in acute spinal cord slices prepared from 21
days old rats, the effect of N-oleoyldopamine (OLDA) application on the frequency of
miniature excitatory postsynaptic currents (mEPSCs) under different temperature
conditions and after protein kinase C (PKC) activation was evaluated. At room
temperature (24°C) high concentration of OLDA (10μM) was needed to increase the
frequency of mEPSCs, while low concentration of OLDA (0.2μM) did not evoke any
change. However, after activation of PKC by phorbol 12-myristate 13-acetate (PMA,
1μM), application of the low concentration of OLDA increased significantly the frequency
of mEPSCs. The control frequency of mEPSCs was increased significantly when the
bath temperature was raised to 34°C. Changes in mEPSCs frequency induced by
OLDA application were similar to those obtained at 24°C. Our results suggest that
central TRPV1 receptors could play an important role in modulation of nociceptive
signalling at the spinal cord level. The presumed endogenous agonists of these
receptors, like OLDA, could have a considerable impact on synaptic transmission at DH
especially under conditions when TRPV1 receptors are phosphorylated.
Supported by GACR 305/06/1115, MSMT LC554, AV0Z 50110509.
42
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
In vitro calcium imaging of spinal cord dorsal horn
neurons
D. SOJKA, J. PALEČEK
Oddělení funkční morfologie, Fyziologický ústav AV ČR
The aim of our study was to develop a technique to study mechanisms of
central sensitization in vitro, on population of dorsal horn neurons. Acute spinal cord
slices (300-400 μm) with spinal roots attached were prepared from rats 12-15 days old.
The slices were incubated with Fluo-4 AM dye. Intracellular calcium concentration
changes were recorded with Leica LSM confocal microscope. Activity of the neurons
evaluated as relative fluorescence changes was evoked by electrical stimulation of the
dorsal rootlet by control stimulation (10 Hz, 1s duration, 0.5ms pulse length). Control
stimulation resulted in increased calcium concentration in number of dorsal horn
neurons. The calcium changes were confirmed as neuron specific by using an in vivo
glial marker sulforhodamine 101 and KCl solution of low and high concentration.
Repeated control stimulations led to consistent changes of calcium concentration in the
neurons recorded. Rate of calcium peak onset and sensitivity to AMPA and NMDA
receptor antagonists CNQX and MK801 and to Ca2+ store depletor caffeine allowed to
distinguish two types of neuronal responses to the stimulation. First type was
potentiated by caffeine, suppressed by CNQX and MK801 coapplication and its calcium
peak onset followed immediately after the stimulation. The second type of calcium
response was highly reduced by caffeine application and the calcium peak onset was
delayed 3 to 8 s after the stimulation. Application of NK1 receptor antagonist decreased
the delayed response to stimulation in number of neurons suggesting involvement of
neurotransmitters of peptidic origin and activation of metabotropic receptors. Both
calcium concentration changes were totally suppressed by application of sodium
channel blocker TTX. Our data suggest possible important role of internal calcium
stores activated by metabotropic receptor pathway in pain transmission and possible
participation of internal stores in induction of the central sensitization.
GACR 305/06/1115, 305/03/H148, AV0Z 5011922, LC 554, MYORES No. 511978.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
43
Chronic constriction injury in weanling rats
S. VACULÍN, M. FRANĚK, R. ROKYTA
Charles University in Prague, 3rd Faculty of Medicine
Dpt. of Normal, Pathological and Clinical Physiology
Neuropathic pain is known to appear in infants and younger children,
however, the incidence is much lower than in school-age children and adults.
Development of neuropathic pain was studied in modified peripheral neuropathic pain
model in weanling rats. In order to evoke pain, two ligations (chronic constriction injury –
CCI) were placed on right sciatic nerve at postnatal day 22. CCI evoked significant
difference in paw withdrawal latency between the hindlimbs in response to thermal
stimulation ten days later. Both non-significant increase of pain threshold in contralateral
limb and non-significant decrease of pain threshold in ligated limb contributed to the
difference. Regarding mechanical stimulation, non-significant difference in paw
withdrawal latency between the hindlimbs was observed. In sham operated rats,
significant difference between the hindlimbs appeared neither in mechanical nor in
thermal stimulation. Our results show that thermal hyperalgesia, but not mechanical
allodynia, develops following modified CCI in weanling rats.
Supported by CN LC554
44
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Quantitative changes of IL-6 protein are presented not
only in the lumbal, but also in the cervical DRG
following unilateral sciatic nerve injury
Z. VESELKOVÁ, P. DUBOVÝ, I. SVÍŽENSKÁ, I. KLUSÁKOVÁ
Department of Anatomy, Division of Neuroanatomy, Medical Faculty, Masaryk
University Brno, Czech Republic
Several lines of evidence suggest that pro- and anti-inflammatory cytokines
contribute to both the induction and maintenance of neuropathic pain derived from
cellular and molecular changes in the DRG including the activity of the primary sensory
neurons.
Interleukin-6 (IL-6) is a pleiotropic cytokine of the family containing IL-11, ciliary
neurotrophic factor (CNTF), cardiotrophin-1 (CT-1), cardiotrophin-like cytokine (CLC),
leukemia inhibitory factor (LIF), oncostatin M. A significant involvement of IL-6 in
neuropathic pain induction and modulation of nerve regeneration is suggested from
several experiments. Chronic constriction injury (CCI) of sciatic nerve is wellcharacterized experimental model of neuropathic pain. We used this model to study
quantitative changes of IL-6 protein in the rat cervical and lumbal DRG. ELISA was
employed to quantify IL6 protein in both ipsi- and contralateral cervical (C-DRG) as well
as lumbal (L-DRG) dorsal root ganglia from naïve rats and those operated for unilateral
CCI of sciatic nerve with periods of survival for 1, 3, 7, and 14 days.
One day after CCI, an increase of IL-6 protein was measured in the ipsilateral
cervical dorsal root ganglia (C-DRGi) with a peak on day 3. On day 14 from operation a
level of IL-6 protein was close to the control baseline level. Contralateral cervical
ganglia (C-DRGc) displayed only a mild decrease of IL-6 protein on day 7. No
significant changes were found in other periods of survival, and the IL-6 protein level
reached to control baseline levels on day 14. In comparison with the naïve DRG, the IL6 protein of ipsilateral lumbal ganglia (L-DRGi) elevated from postoperation day 1, and
the higher level of IL-6 remained up to 14 days from operation. The IL-6 protein level in
the contralateral lumbal ganglia (L-DRGc) peaked on day 3, and enhanced level was
measured till 14 days.
These data provide evidence for changes of IL-6 protein levels not only in the
DRG associated with damaged nerve, but also in the DRG non-associated with nerve
injury in the rat experimental neuropathic pain model.
Supported by GACR 309/07/0121 and MSM0021622404.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
45
Engraftment of donor cells in CNS depends on proper
timing of host irradiation after preconditioning with
cyclophosphamide
P. JIROUTEK, L. ŠEFC
Neurologická klinika VFN a 1.LFUK, Ústav patologické fyziologie 1.LFUK
INTRODUCTION
The presence of donor bown marrow (BM) derived cells in CNS seems to have
neuroprotective effect in animal models of various neurological disorders. The positive
effect of BM transplantation or human umbilical cord blood transplantation was
observed in mice model of ALS, ischemic brain lesion and traumatic spinal cord lesion.
We believe that the crutial factor in the process of neuroprotection madiated by BM
derived cells is the long term survival of the donor cells in CNS.
AIM
We studied the factors that affect the long term survival of BM derived donor cells in
host CNS after BM transplantation. We have tested the hypothesis that the successful
BM engraftment is one of the most important features that increses the pool of donor
cells in host CNS.
METHODS
Three gopups of C57BL/6 mice were irradiated (4Gy, whole body irradiation) and
transplanted with GFP+ BM (4*10exp6 nucleated cells). Group CY2 was preconditioned
with cyclophosphamide (CY) (135mg/kg bw) two days before the BM transplantation
(BMT) and group CY5 five days before the BMT. No CY was administrated in the
control group. We evaluated the time course of BM chimerism and the number of GFP+
cells in the host CNS twelve month after BMT. The changes of microenvironment in BM
after CY administration were analysed properly.
RESULTS
The number of CFU-S in BM after CY administration fell rapidly to its minimum of 10%
on day 1 and raised again to the local maximum of 70% on day 3 and than decreased
slowly. Percentage of CFU-S in S phase increased to its maximum (52%) on day 2 and
reached the minimum on day 5, where almost none (1%) CFU-S in S phase were
detected. The BM chimerism reached 87% in CY5 group, 25% in CY2 and 29% in the
control group.
In the CNS the density of GFP+ cells (10exp-8/μm2) was 8.98 (p<0.001) in CY5 group,
1.44 in CY2 group and 1.60 in the control group.
CONCLUSION
The timing of BMT after preconditioning with CY strongly influence the BM engraftment.
The microenvironment of high proliferating CFU-S on day 2 after CY administration
probably interferes with the ability of the donor cells to keep in the BM in contrast to the
BMT performed on day 5. The degree of BM chimerism strongly correlates with the long
time presence of donor cells in CNS. Successful BM engaftment seems to be an
important factor for maintaining the donor cells pool in CNS after BMT.
46
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Electrophysiological characterization of D6/GFPneural stem/progenitor cells during in vitro
differentiation and after transplantation into the
injured rat brain
M. ANDĚROVÁ1,3, I. PRAJEROVÁ1,2, P. HONSA1, O. MACHON4, A. CHVÁTAL1,2,3
1
Laboratory of Neurobiology, Dept. of Cellular Neurophysiology, Institute of
Experimental Medicine, ASCR
2
Department of Neuroscience, 2nd Med. Faculty, Charles University
3
Center for Cell Therapy and Tissue Repair, Charles University
4
Department of Transcriptional Regulation, Institute of Molecular Genetics, ASCR;
Prague, Czech Republic
D6 is a promotor/enhancer of the mDach1 gene, which is involved in the
development of the neocortex, including the ventricular zone and hippocampus, and is
expressed in the proliferating neural stem/progenitor cells of the cortex (Machon et al.,
2002, Neuroscience 4, 951-966). The differentiation potential of embryonic neural
stem/progenitor cells isolated from the cortex of E12 mouse embryos, in which the
expression of GFP is driven by the D6 promoter was, studied in vitro and after
transplantation into non-injured adult rat brain as well as into the site of a cortical
photochemical lesion. The electrophysiological properties of D6/GFP cells were studied
using the whole-cell patch-clamp technique, and immunohistochemical analyses were
carried out. Six days after the onset of in vitro differentiation, two cell populations were
identified. Large flat cells forming an underlying layer expressed GFAP and/or nestin.
Their average membrane potential (Vm) was -78.3 mV, membrane resistance (IR) 89.9
MOhms and membrane capacitance (Cm) 37.3 pF, and they displayed large passive K +
currents. Smaller cells with multiple long processes expressed neuronal markers such
as βIII tubulin, MAP-2 or DCX. These cells, with Vm of -61.2 mV, IR of 909.5 MOhms
and Cm of 11.2 pF, expressed fast activating A-type K+- channels, delayed outwardly
rectifying K+ channels and TTX -sensitive Na+-channels. One week after transplantation
into intact tissue and 4 weeks after transplantation into the site of a photochemical
lesion, the D6/GFP-cells survived and expressed markers characteristic of mature
neurons, such as NeuN, NF68, βIII tubulin and MAP2 and they displayed typical
neuronal curent pattern. Based on these results, D6/GFP-cells could provide a suitable
tool for studying neurogenesis in vivo as well as neural stem/progenitor cell survival,
migration and differentiation under pathological conditions.
Supported by GACR305/06/1316, AVOZ50390512, LC554, 1M0538 and
GAUK62/2006/C/2.LF.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
47
Differentiation of neural stem cells expressing Sonic
Hedgehog and Wnt-7a
I. PRAJEROVÁ1, P. HONSA1, M. ANDĚROVÁ1,3, A. CHVÁTAL1,2,3
1
Laboratory of Neurobiology, Inst. Exp. Med., ASCR
Dept. Neurosci. and
3
Center for Cell Therapy and Tissue Repair 2nd Medical Faculty, Charles University;
Prague, Czech Republic
2
Sonic hedgehog (Shh) and Wnt-7a are secreted morphogens involved in
neurogenesis of the adult brain. GFP-labeled P0 mouse neural stem cells expressing
either Shh (Shh/GFP) or Wnt-7a (Wnt-7a/GFP) were used to study their effect on neural
stem cell proliferation and differentiation in vitro. Electrophysiological characterization
using the patch-clamp technique and immunohistochemical analysis were carried out 8
days after the induction of differentiation by retinoic acid; wild-type cells (WT/GFP) were
used as a control. In WT/GFP cells three distinct cell populations were identified. Large
flat cells with a cell-body diameter of 40µm formed an underlying layer (19%),
expressed GFAP, and displayed passive, time- and voltage-independent K+ currents,
with an average membrane potential (Vm) of -87 mV and input resistance (IR) of
61MOhms. The second population of cells (16%) with a triangular cell-body (diameter
25 µm) expressed GFAP or NG2 and predominantly displayed passive, time- and
voltage-independent K+ currents together with an inwardly rectifying current activated by
hyperpolarization. Their mean Vm and IR were -90 mV and 72 MOhms, respectively.
The third group of cells (65%) with a cell-body diameter of 15µm (termed neuron-like
cells) were MAP-2, DCX or β-III tubulin positive with a mean Vm of -83 mV and IR of
357 MOhms and mostly displayed voltage-dependent KA, KDR and TTX-sensitive Na+
currents (INa). Shh expression led to increased numbers of both flat and triangular cells,
but their passive membrane properties were not significantly different from those in
control cells. The number of neuron-like cells decreased by 25%, and moreover, INa
currents were not detected. In Wnt-7a/GFP cells the number of large flat cells was
decreased by 16% and the number of triangular cells increased by 23%, while the
number of neuron-like cells was not significantly different when compared to controls.
All three cell populations showed increased IR and decreased Vm; further, in neuronlike cells the INa amplitude was significantly increased. Based on electrophysiological
data we can conclude that Wnt-7a/GFP cells showed marked differences compared to
Shh/GFP and WT/GFP cells, thus these morphogens might play an important role in
postnatal neural stem cell differentiation.
Supported by GACR 305/06/1316, GAUK62/2006/C/2.LF, AVOZ50390512, LC554 and
1M0538.
48
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Ischemia-induced Volume Changes in Astrocytes: The
Role of Chloride Movement
J. BENEŠOVÁ1, M. ANDĚROVÁ1,3, M. HOCK4, O. BUTENKO1,2, I. PRAJEROVÁ1,2,
A. CHVÁTAL1,2,3
1
Laboratory of Neurobiology, Department of Cellular Neurophysiology, Institute of
Experimental Medicine, AS CR, Prague, Czech Republic
2
Department of Neuroscience, Charles University, 2nd Medical Faculty, Prague, Czech
Republic
3
Center for Cell Therapy and Tissue Repair, Charles University, Prague, Czech
Republic
4
Department of Epithelial Physiology, Institute of Physiology, AS CR, Prague, Czech
Republic
Volume changes of eGFP-labeled astrocytes during ischemia/reperfusion in
situ were studied in the cortex of GFAP/EGFP transgenic mice using confocal
microscopy combined with 3D reconstruction. Inhibitors of chloride channels (NPPB,
DIDS, Cd2+, tamoxifen), the K-Cl cotransporter (DIOA) and the Na-K-Cl cotransporter
(bumetanide) were used to study the contribution of chloride movement to cell volume
changes and regulatory volume processes. A 20-minute application of a solution
modelling oxygen-glucose deprivation (OGD) revealed two populations of astrocytes:
low response (LR) astrocytes and high response (HR) astrocytes. In LR-astrocytes, the
application of OGD led to a small volume increase of 5%; subsequent 40-minute
reperfusion led to complete volume recovery. In HR-astrocytes, the application of OGD
evoked a marked volume increase of 41%; reperfusion led within the first 20 minutes to
an additional volume increase with no apparent volume recovery. OGD application
together with NPPB, DIDS or tamoxifen led to a smaller volume increase compared to
OGD alone, while bumetanide and DIOA had no effect on the volume changes evoked
by OGD. The application of DIDS, NPPB, Cd2+, tamoxifen or bumetanide during
reperfusion evoked a significant volume decrease. A pH shift from 7.4 to 6.8, modeled
by ACSF (artificial cerebrospinal fluid) saturated with 85% O 2 / 15% CO2 (ACSFpH) or
by the addition of lactic acid, caused a volume decrease of 15% or 25%, respectively.
Two populations of astrocytes were not detected during the shift of pH, as all measured
cells displayed consistent volume changes. NPPB, DIDS, Cd2+, or bumetanide applied
together with ACSFpH reduced the volume decrease induced by pH 6.8, while
tamoxifen evoked a volume increase. When applied during reperfusion, DIDS and Cd2+
caused cell swelling, NPPB and bumetanide did not affect cell volume and tamoxifen
significantly inhibited volume recovery. Our data suggest the presence of two
populations of astrocytes in the cortex of GFAP/EGFP mice that respond differently to
ischemia and also imply an essential role for Cl– movement, carried by the Na-K-Cl
transporter and Cl– channels, in volume regulation.
Supported by GACR305/06/1316, GACR305/06/1464, AVOZ50390512, LC554 and
1M0538
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
49
Changes in the expression of K+ and Na+ channels in
astrocytes and NG2 glia after ischemia in vivo
H. NEPRAŠOVÁ, M. ANDĚROVÁ, J. BENEŠOVÁ, O. BUTENKO, A. CHVÁTAL
Department of Cellular Neurophysiology, Inst. of Experimental Medicine, Academy of
Sciences of the Czech Republic and Center for Cell Therapy and Tissue Repair, 2nd
Medical Fac., Charles Univ., Prague, Czech Republic
Time-dependent changes of astrocyte and NG2 glia membrane properties
were studied together with tissue damage and glial scar formation in hippocampus (CA1
region) of 8-week-old rats after global cerebral ischemia followed by reperfusion for 2, 6,
24 hours, 3, 7 and 35 days. Glia membrane properties were determined by the wholecell patch-clamp technique and tissue damage in the CA1 region was evaluated using
markers of neurons, glia, newly derived cells, apoptosis and proliferation. In both shamoperated rats and those after ischemia, astrocytes from the CA1 region displayed
passive symmetrical non-decaying K+ currents with the additional expression of delayed
outward K+ rectifier (KDR) and/or inward K+ rectifier (KIR) currents. NG2 glia displayed a
complex current pattern, i.e. KDR, KIR, A-type K+ current and voltage-dependent Na+
currents (INa). Astrocyte depolarization was observed starting 2 hours after ischemia
and their membrane capacitance was decreased from the first day after ischemia. The
KIR current density in astrocytes was increased 6 hours after ischemia, when apoptotic
markers appeared in neurons. After 5 weeks of reperfusion, apoptotic markers in CA1
astrocytes were detected, coinciding with an increase in the KDR current density. In
NG2 glia, an increase in KDR, KIR and INa was observed 6 hours to 1 day after
ischemia. Proliferation of NG2 glia was observed during the first week after ischemia.
Moreover, NG2/nestin double positive cells were found in CA1 region 3D and 7D after
ischemia. Our data show that global cerebral ischemia results in changes typical of
neuronal damage and astrogliosis in the CA1 region. Transient changes in membrane
properties and expression of voltage-dependent K+ and Na+ channels occur both in
astrocytes and NG2 glia and correlate with proliferation and nestin expression in NG2
glial cells.
Supported by GACR 305/06/1316, 305/06/1464, AVOZ50390512, LC554, 1M0538.
50
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Human embryonic stem cells (CCTL14) differentiate
into a neuronal phenotype
N. KOZUBENKO1, M. KAPCALOVÁ1, M. ANDĚROVÁ1, O. BUTENKO1, A. HAMPL1,2,3,
P. JENDELOVÁ1,2, E. SYKOVÁ1,2
1
Institute of Experimental Medicine ASCR, Prague, Czech Republic
Department of Neuroscience and Center for Cell Therapy and Tissue Repair, Charles
University, Second Medical Faculty, Prague, Czech Republic
3
Faculty of Medicine, Masaryk University, Brno, Czech Republic
2
Human embryonic stem cells (hESCs) demonstrate remarkable proliferative
and developmental capacity. Clinical interest arises from their ability to provide an
apparently unlimited cell supply for transplantation and from the hope that they can be
directed to desirable phenotypes in high purity. The CCTL 14 ES cell line (derived by
the Department of Molecular Embryology, Institute of Experimental Medicine, Academy
of Sciences of the Czech Republic) has been cultivated in vitro for extended periods
while maintaining the expression of markers characteristic of pluripotent primate cells
(Nanog, Oct-3/4, SSEA-4). The karyotype was stable during the entire time of the
experiments. We induced embryoid body (EB) formation using a Noggin (500 ng/ml) –
4/+4 classical protocol and then a cocktail of basic fibroblast growth factor (bFGF) (20
ng/ml) and epidermal fibroblast growth factor (EGF) (20 ng/ml) during the next 8 days.
Subsequently, the extent of neural differentiation in the EBs was assessed by analyzing
the percentage of cells expressing markers of neural precursors, including neural cell
adhesion molecule (NCAM) and Nestin. The percentage of NCAM- and Nestin-postive
cells was 95.52.3% and 96.12.8%, respectively. Neuronal differentiation was induced
by culturing the dissociated EBs on poly-D-lysine/laminin in growth medium
supplemented with bFGF (10 ng/ml), NT-3 (10 ng/ml), brain-derived neurotrofic factor
(10 ng/ml), insulin-like growth factor (1 ng/ml) and ascorbic acid (160 M) for 4 weeks.
During 14 days, cells displayed the morphology and also expressed the structural
markers of immature neurons such as -III-tubulin and PSA-NCAM. The finally
differentiated cells expressed mature neuronal markers – NF160, MAP-2 and
synaptophysin. Some cells were positive for glutamate and -aminobutyric acid (GABA).
Electrophysiological recording of cell membrane currents indicated the presence of
mature functional neurons in differentiated culture. These cells had sodium channels,
responded to GABA and fired action potentials. We have developed a basic platform for
the efficient and directed differentiation of hESCs and a potential source of cells for use
in transplantation studies.
Supported by AVOZ50390703, 1M0538, LC554
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
51
Properties and growth of human bone marrow
mesenchymal stem cells in different media
K. TURNOVCOVÁ, K. RŮŽIČKOVÁ, P. JENDELOVÁ, E. SYKOVÁ
Institute of Experimental Medicine, ASCR, and Department of Neuroscience, Charles
University, 2nd, Medical Faculty, Prague.
Human mesenchymal stem cells (hMSCs) are mutipotent cells with the
capacity to differentiate into various cell types such as osteoblasts, chondroblasts or
myoblasts. Moreover, they have the ability to differentiate into non-mesenchymal cell
phenotypes such as astrocytes or neurons. Therefore, hMSC can be an important tool
for cell therapy and tissue engineering. The application of hMSCs in clinical medicine
requires rapid cell expansion in media suitable for clinical use. For this reason, we
tested the influence of several culture media on cell expansion and cell properties. In
our study we examined the colony-forming properties (CFU - colony forming unit test),
the doubling time (PD - population doublings) and cell cycle and the expression of
surface markers. We isolated hMSCs from bone marrow obtained from healthy donors;
the mononuclear fraction was collected using a Ficoll-gradient. Cells were seeded and
expanded in different culture media: α-MEM (Gibco) containing penicilin/streptomycin
with 2.5%, 5%, 10% or 20% fetal bovine serum (FBS), 5% or 10% human cord blood
serum (hCBS), 5% or 10% human blood serum from AB adult donors (hABS) or hMSCmedium (Lonza).
We assesed the colony-forming properties by counting colonies with a
diameter > 2 mm and calculating the total area of the colonies. The colony forming
efficiency was best in -MEM/hCBS and -MEM/hABS, good in hMSC-medium and
worse in -MEM/FBS. Among FBS-containing media, a 10% concentration was the best
and 2.5% and 20% the worst. The shortest time for PD was achieved in media enriched
with human sera - 10% hABS followed by 5% hABS and hMSC-medium - and it
gradually increased from 10% hCBS to -MEM/FBS. The cell cycle was examined using
BD Pharmingen PI/Rnase Buffer and assesed by FACS analysis. In all samples the
proliferating fraction (S+G2/M) was < 10%, independently of the media used.
Phenotyping of 16 surface markers was performed with a FACSAria: CD10, CD 29,
CD34, CD44, CD45, CD49a, CD61/51, CD71, CD73, CD90, CD105, CD235a, CD271,
MHC-I, MHC-II and fibroblast surface marker. CD34, CD45, CD235a, CD271 and MHCII were negative and CD 90, CD105 and MHC-I were strongly positive with all tested
media. CD10, CD29, CD44, CD49a, CD51/61, CD71 and fibroblast surface marker
showed broad variability in α-MEM/hABS and hMSC-media. The expression of CD29,
CD44 and CD73 decreased with lower concentrations of serum. The choice of serum
influences hMSC expansion and cell properties; hABS seems to be a promising
candidate for hMSC cell expansion in clinical use.
Supported by NR8339-3, AV0Z50390703, 1M0538, LC554
52
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Co-transplantation of olfactory ensheathing cells and
mesenchymal stem cells improves hindlimb
performance after spinal cord injury but does not
show synergistic benefits
T. AMEMORI, K. RŮŽIČKOVÁ, G.D. ARBOLEDA TORO, P. JENDELOVÁ, E. SYKOVÁ
Institute of Experimental Medicine, ASCR, and Center for Cell Therapy and Tissue
Repair, Charles University, 2nd Med. Faculty, Prague, Czech Republic
Olfactory ensheathing cells (OECs) and mesenchymal stem cells (MSCs)
have been used as promising candidates for transplantation therapy in the central
nervous system. OECs are known as glial cells residing in the lamina propria of the
olfactory mucosa and in the outermost layer of the olfactory bulb and the surrounding
olfactory receptor neurons, which have a continuous turnover throughout life. MSCs
have the pluripotency to differentiate into cells of mesenchymal origin and neurons.
OECs express several growth factors and extracellular matrix molecules that provide a
hospitable environment for both injured and remaining intact axons in the spinal cord
and that promote axonal regeneration. MSCs produce growth factors and cytokines and
excert their neuroprotective effects on neurons and oligodendrocytes by downregulating
Caspase-3-mediated apoptosis after spinal cord injury (SCI). The transplantation of
other cell types along with OECs benefits SCI treatment by inducing more effective
neurotrophic support. In our study, the effects of OEC and/or MSC transplantation were
examined. Both cell types are appropriate for autologous transplantation therapy. OECs
were isolated from the lamina propria and MSCs from the bone marrow of one-monthold male Wistar rats. SCI was made 1 cm anterior to T10 by balloon inflation in adult
male Wistar rats. One week after SCI, a total of 3x105 OECs and/or MSCs were
transplanted into the injured spinal cord through a glass pipette connected to an
automatic microinjector. Control rats received saline instead of cells. Hindlimb locomotor
activity was assessed weekly by the Baso, Beattie, and Bresnahan (BBB) test. Motor
evoked potentials (MEPs) were tested every week by transcranial electric stimulation.
BBB scores improved in transplanted rats, but the results following co-transplantation of
OECs and MSCs did not differ significantly from those following transplantation of one
cell type alone. MEPs drastically decreased their amplitude from about 6mV to about
20μV following contusion and recovered partially, but never regained normal values
throughout the experiments. OECs and MSCs obtained from green fluorescent protein
transgenic rats showed that both types of cells survived in the spinal cord lesions, but
did not migrate far from the injection sites during two months observation. Although
OECs and MSCs had the ability to foster hindlimb recovery, the co-transplantation of
both types of cells did not reveal any additional benefit.
Supported by AVOZ50390703, LC554, 1M0538, 1A8697-5, GAČR309/06/1246.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
53
Mobilization of bone marrow cells induced by G-CSF
and FLT3 ligand
K. LIKAVČANOVÁ1, L. URDZIKOVÁ1, J. ŠEDÝ1, P. JENDELOVÁ1,2, E. SYKOVÁ1,2
1
Institute of Experimental Medicine, ASCR
Center for Cell Therapy and Tissue Repair and Department of Neuroscience, Charles
University, 2nd Medical Faculty, Prague, Czech Republic
2
Our previous studies showed that mobilization of bone marrow cells with
granulocyte colony stimulating factor (G-CSF) or FLT3 ligand or a combination of GCSF and FLT3 ligand improved the motor performance and sensitivity of rats with spinal
cord injury in comparison with saline-treated animals. The sensitivity improvement
caused by combined therapy (at the same total dose) was significantly greater than that
resulting from treatment with either G-CSF or FLT3 ligand alone. Morphometric
measurements showed that treatment with G-CSF, FLT3 ligand or a combination of GCSF and FLT3 ligand also increased the spared white and gray matter, evaluating the
cross-sectional area as well as the volume of the spinal cord lesion. We studied the
increase in peripheral blood monocytes during and after the injection of G-CSF, FLT3
ligand or a combination of G-CSF and FLT3 ligand. Wistar male rats were divided into
four groups. The first group received FLT3-ligand (50 µg/kg, i.v., n = 6) for five days, the
second group was injected with G-CSF (50 µg/kg, i.v., n = 6), the third group received a
mixture of G-CSF and FLT3-ligand (G-CSF 25 µg/kg + FLT3 25 µg/kg, i.v., n = 6) and
the fourth group was injected with saline (1ml/kg, i.v., n = 5). Blood samples (0.5-1.0
ml) were taken from the eye orbital sinus of each animal under isofluorane anesthesia
one day before bone marrow stimulation, on the 1st, 2nd and 4th day of stimulation, and
on the 2nd and 4th day post-stimulation. For cell counting we used a standard
hematology analyzer. G-CSF and a combination of G-CSF and FLT3 ligand increased
the absolute number of leukocytes (Lkc) during the time course of bone marrow
stimulation. Lkc subpopulation ratios changed according to the injected drugs. The
relative number of lymphocytes (Ly) was decreased and the number of neutrophils (N)
increased in animals with G-CSF injection during the bone marrow stimulation period
and on the 4th day post-stimulation. However, FLT3 ligand injection decreased Ly and
increased N subpopulations only after bone marrow stimulation was completed. The
combination of both factors lowered Ly and increased N subpopulations during bone
marrow stimulation and post-stimulation. The observed improvement in behavioral and
morphological parameters in animals with SCI treated with a combination of both drugs
could be explained by the prolonged time course of the mobilization of bone marrow
cells.
Supported by GACR 309/06/1246, 1A8697-5, AVOZ503905703, 1M0538, LC554
54
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Experimental spinal cord injury reconstruction using
hydrolytically degradable hydrogels
A. HEJČL1,2,4 , P. LESNÝ1,2, J. ŠEDÝ1,2, M. PŘÁDNÝ2,3, J. MICHÁLEK2,3,
P. JENDELOVÁ1,2, E. SYKOVÁ1,2
1
Institute of Experimental Medicine, Academy of Sciences of the Czech Republic,
Prague, Czech Republic
2
Department of Neuroscience and Center for Cell Therapy and Tissue Repair, Charles
University, 2nd Faculty of Medicine, Prague, Czech Republic
3
Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic,
Prague, Czech Republic
4
Department of Neurosurgery, Masaryk Hospital, Usti nad Labem, Czech Republic
Spinal cord injury leads to axonal damage, necrosis, demyelinization and
extracellular matrix deposition, which ultimately lead to the formation of a glial scar and
post-traumatic pseudocystic cavities. Three-dimensional biocompatible macroporous
polymer hydrogels can be utilized in experimental models of spinal cord injury repair.
They bridge the pseudocystic cavity and provide a scaffold for the ingrowth of
regenerating axons. The advantage of using degradable hydrogels is that they may
bridge the lesion and provide a scaffold for axonal regeneration without leaving any
remnants of artificial material several months after implantation. Three types of
hydrolytically degradable hydrogels based on copolymers of 2-hydroxypropylmethacrylamide (HPMA) with degradation times of 18, 23 or 32 days, with decreasing
hydrophility in the same order, were prepared and implanted into a spinal cord
hemisection in rats. The animals were sacrificed one or two months after implantation,
and their spinal cords were histologically evaluated. One month after implantation, all of
the hydrogels integrated well into the spinal cord tissue, with only minimal signs of
foreign body reaction. We observed loose mesenchymal tissue with ingrowing
connective tissue elements, blood vessels and neural processes in all of the hydrogels.
The ratio between neural processes and connective tissue was highest in the hydrogel
with the highest hydrophility. Two months after implantation, the ingrowth of the neural
processes continued only in the hydrogels degradable within 23 or 32 days, in which
pseudocystic cavities were minimal. The hydrogel with the shortest degradation time (18
days) was resorbed, and large pseudocystic cavities had developed. Hydrophilic
degradable hydrogels may be utilized for spinal cord tissue reconstruction. However,
the stability of newly formed tissue is insufficient when the degradation time is less than
3 weeks.
Supported by: AVOZ50390703, 1M0538, GAČR309/06/1246, 1A8697-5/2005, LC554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
55
Growth of rat mesenchymal stem cells on layers of
nonwoven nanofibers from different biocompatible
polymers
M. KAPCALOVÁ1,2, P. LESNÝ1,2, P. JENDELOVÁ1,2, L. MARTINOVÁ3, E. SYKOVÁ1,2
1
Institute of Experimental Medicine Academy of Sciences of the Czech republic, Prague,
Czech Republic
2
Deparment of Neuroscience and Center for Cell Therapy and Tissue Repair, Charles
University, Second Medical Faculty, Prague, Czech Republic
3
Department of Nonwovens, Technical University of Liberec, Czech Republic
The importance of biomaterials has steadily increased in recent years, while
the number of polymer applications in tissue engineering continues to grow. Polymeric
scaffolds created from nonwoven electrospun nanofibers have the potential to be used
in the reconstruction of skin, bones, muscles, veins and nerves, supporting the growth
of cell cultures utilized in cell therapies. Multipotent mesenchymal stem cells play an
important role in stromal support for hematopoietic stem cells, immune modulation, and
tissue regeneration.
We studied the effect of nanofiber surface chemistry on the growth of rat bone
marrow mesenchymal stem cells (rMSCs). We compared nanofiber layers with similar
morphological structure, created from different biocompatible polymers (polyamide 6,
methacrylate copolymer, poly(lactic-co-glycolic) acid and polyurethane). The nanofiber
layers were prepared by electrospinning on a NanospiderTM device (ELMARCO and
Technical University of Liberec). As a negative control, we utilized polystyrene tubes;
the positive control was polystyrene modified for tissue culture (cell culture wells; both
from Techno Plastic Products). We studied the growth of rMSCs, isolated from rats
expressing green fluorescent protein (GFP), in Dulbeccos modified Eagle medium
(DMEM) supplemented with 10 fetal bovine serum (FBS) and primocin (2 lml) on the
nanofiber layers and control surfaces. The rMSCs were scanned on the first and third
days after seeding, and the cellular density was determined using the Cavalieri principle
within MATLAB software (The MathWorks, Inc.). The GFP-rMSCs grew on all of the
nanofiber surfaces significantly better than on the unmodified polystyrene; however,
their growth was less than on the tissue culture polystyrene. The results show that
although rMSCs adhered to all of the nanofiber layers, the chemical composition of the
fibers plays a role in their adhesion. The highest cellular density was measured on the
polyamide 6 nanofiber layers, the lowest on the polyurethane nanofiber layers.
Biocompatible polymer nanofibers can be utilized as cell carriers for tissue
reconstruction; however, further studies are necessary in order to determine the best
polymer structure.
Supported by GACR 309/06/1246, 2B06130, 1A8697-5, AVOZ503905703, LC554,
1M0538
56
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Nonwoven nanofiber materials as three-dimensional
tissue constructs in spinal cord injury
P. LESNÝ1,2,3, O. JIRSÁK4, P. JENDELOVÁ1,2,3, J. MICHÁLEK3,5, M. PŘÁDNÝ3,5, L.
MARTINOVÁ4, E. SYKOVÁ1,2,3
1
Institute of Experimental Medicine AS CR, Prague
Department of Neuroscience, Charles University, 2nd Medical Faculty, Prague
3
Center for Cell Therapy and Tissue Repair, Charles University, 2nd Medical Faculty,
Prague
4
Department of Nonwovens, Faculty of Textile Engineering, Liberec
5
Institute of Macromolecular Chemistry AS CR, Prague
2
The preparation of three-dimensional tissue replacements for bridging a
spinal cord lesion is at the center of attention of tissue engineering. Polymeric scaffolds
created from nonwoven electrospun nanofibers support the growth of various supportive
cell types utilized in the treatment of spinal cord injury, such as bone marrow stromal
cells (MSC) or olfactory ensheathing glial cells (OEGs). It is therefore possible to create
three-dimensional implants by folding the cell-containing layers. Using a Nanospider
device (International patent WO 2005/024101, Technical University of Liberec), we
prepared layers from the copolymer of 2-hydroxyethylmethacrylate and
ethoxyethylmethacrylate with mesenchymal stem cells (MSCs) or olfactory glial cells
(OEGs) growing on these layers. The growth of the cells was evaluated using confocal
microscopy. After reaching confluence, the individual layers were folded, gently
compressed and implanted into a spinal cord lesion. In culture, MSCs grew to
confluence on all of the nanofiber layers, while OEGs remained in a subconfluent state.
The cell-containing folded scaffolds were implanted into hemisected rat spinal cords.
After two weeks, the nanofiber scaffold containing the cells had adhered to the host
tissue; the MSCs were able to leave the implant and migrate into the host tissue. There
were neural cell processes stained for neurofilaments present in the implanted scaffold;
however, astrocytes did not enter the implants. Our results show that nonwoven
polymeric nanofiber scaffolds can be utilized in vitro to cultivate MSCs and OEGs; these
scaffolds seeded with cells have the ability to induce tissue formation when implanted
into injured spinal cord tissue and therefore support the regeneration of the nervous
tissue. The implantation of nonwoven polymeric nanofiber scaffolds may serve as an
alternative to conventional grafting technologies.
Supported by 2B06130, AVOZ50390703, 1M0538 GACR309/06/1246, 1A8697-5,
LC554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
57
Development of neurogenic pulmonary edema in
spinal cord injured rats – the role of isoflurane
anesthesia
J. ŠEDÝ1,2, L. URDZIKOVÁ1, K. LIKAVČANOVÁ1, A. HEJČL2, M. BURIAN2,3,
P. JENDELOVÁ1,2, J. ZICHA4,5, J. KUNEŠ4,5, E. SYKOVÁ1,2
1
Institute of Experimental Medicine, ASCR, Prague, Czech Republic
Center for Cell Therapy and Tissue Repair and Department of Neuroscience, Second
Faculty of Medicine, Charles University, Prague, Czech Republic
3
MR-Unit, Radiology Department, Institute for Clinical and Experimental Medicine,
Prague, Czech Republic
4
Institute of Physiology, ASCR, Prague, Czech Republic
5
Center for Cardiovascular Research, Prague, Czech Republic
2
Anesthetics can either promote or inhibit the development of neurogenic
pulmonary edema (NPE) after central nervous system injury. The influence of isoflurane
was examined in male Wistar rats using 1.5%, 2%, 2.5%, 3%, 4% or 5% isoflurane in
air. Epidural balloon compression of the thoracic spinal cord was performed. The
development of NPE was examined in vivo and on histologic sections of lung tissue.
Animals anesthetized with 1.5% or 3% isoflurane were behaviorally monitored using the
BBB and plantar tests for 7 weeks post-injury. The spinal cord was examined using MRI
and morphometry of the spared white and gray matter. All animals from the 1.5% and
2% groups developed NPE. Almost 42% of the animals in the 1.5% group died of
severe pulmonary hemorrhage and suffocation; X-rays, the pulmonary index and the
histological picture revealed a massive NPE. More than 71% of the animals from the
2.5% and 3% groups did not develop any signs of NPE. Blood pressure after spinal cord
compression rose more in the 1.5% group than in the 3% one. In the 1.5% group,
sympathetic ganglionic blockade prevented neurogenic pulmonary edema development.
Animals from the 3% group recovered behaviorally more rapidly than did the animals
from the 1.5% group; morphometry and MRI of the lesions showed no differences.
Thus, low levels of isoflurane anesthesia promote NPE in rats with a compressed spinal
cord and significantly complicate their recovery. The optimal concentration of
anesthesia for performing a spinal cord compression lesion is between 2.5 and 3%
isoflurane in air. A concentration of 1.5-2% isoflurane anesthesia can be used as a
model of severe NPE in rats with balloon-induced spinal cord injury.
Grant support: AV0Z50390512, AV0Z50110509, 1M0538, LC554, GACR309/06/1246,
IGA MZ 1A8697-5, IGA MZ NR/8339-3, 1M0510 and the EC FP6 project RESCUE
(LSHB-CT-2005-518233).
58
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Extracellular space diffusion parameters in focal
cortical dysplasia
A. HOMOLA1,2, L. VARGOVÁ1,2, J. ZÁMEČNÍK3, P. KRŠEK4, P. MARUSIČ5,
E. SYKOVÁ1,2
1
Department of Neuroscience and Center for Cell Therapy and Tissue Repair, Charles
University, 2nd Medical Faculty, Prague, Czech Republic
2
Institute of Exp. Medicine, ASCR, Prague, Czech Republic
3
Department of Pathology and Molecular Medicine, Charles University, 2nd Medical
Faculty, Prague, Czech Republic
4
Department of Pediatric Neurology, Charles University, 2nd Medical Faculty, Prague,
Czech Republic
5
Department of Neurology, Charles University, 2nd Medical Faculty, Prague, Czech
Republic
Focal cortical dysplasia is a common cause of pharmacoresistant epilepsy,
but the mechanisms of enhanced excitability in the dysplastic neuronal network are
poorly understood. In this study we determined the extracellular space (ECS) diffusion
parameters in human neocortical tissue, obtained from 16 surgically treated patients
with temporal lobe epilepsy. The ECS diffusion parameters - volume fraction  ( =
ECS volume/total tissue volume) and tortuosity  (2 = free/apparent diffusion
coefficient) - were determined by the real-time iontophoretic method using ion-selective
microelectrodes. Diffusion measurements were performed in 400 μm thick slices, which
were subsequently histologically processed; three categories of cortical malformations
were determined by microscopic analysis: 1) cortex with normal cytoarchitecture, 2)
focal cortical dysplasia (FCD) type I and 3) FCD type II. In tissue with normal
cytoarchitecture,  = 0.24 ± 0.01 and  = 1.48 ± 0.01 (mean ± SE, n = 10 patients, N =
44 slices), which are not significantly different from those values found previously in
healthy human cortex. In both FCD I and FCD II slices, tortuosity was significantly
increased (1.57 ± 0.01, n = 4, N = 11 and 1.67 ± 0.02, n = 3, N = 10, respectively).
Extracellular volume fraction  was not significantly changed in FCD I but was
increased in FCD II (0.27 ± 0.04), reaching in some locations values of 0.35-0.45.
Histological evaluation revealed the disordered structural organization of neuronal and
astrocytic processes, typical for dysplastic cortex, and increased staining for tenascin C.
We conclude that diffusion in dysplastic cortical areas is compromised due to increased
diffusion barriers manifested by an increase of tortuosity. Together with structural
disorganization, the impaired diffusion of neuroactive substances may contribute to the
development of epileptic seizures.
Supported by AVOZ 50390512, 1M0538, GACR 309/04/0753.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
59
Diffusion parameters in the rat cerebral cortex during
pilocarpine-induced status epilepticus
L. DMYTRENKO, K. ŠLAIS, I. VOŘÍŠEK, E. SYKOVÁ
Institute of Experimental Medicine ASCR and Department of Neuroscience, Charles
University, Second Medical Faculty, Prague, Czech Republic
Extrasynaptic transmission between nerve cells, mediated by the diffusion of
neuroactive substances in the extracellular space (ECS), is an alternative mode of
signal transmission that may modulate synaptic transmission itself and thus affect tissue
excitability. The aim of this study was to determine the diffusion parameters in vivo in
the brain cortex of 3-month-old male Wistar rats after pilocarpine-induced seizures.
Animals were pretreated with lithium chloride 14-18 hours before the experiment,
anesthetized by urethane and artificially ventilated. The epileptiform seizures were
evoked by pilocarpine administration (300 mg/kg, i.p.). Volume fraction  ( = ECS
volume/total tissue volume) and tortuosity  (2 = D/ADC, where D is the free and ADC
is the apparent diffusion coefficient) were determined from concentration-time profiles of
tetramethylammonium (TMA) applied by iontophoresis, and the apparent diffusion
coefficient of water (ADCw) was measured by diffusion-weighted magnetic resonance
imaging (DW-MRI). ADCw maps were evaluated in the primary somatosensory cortical
region, corresponding to the site of the TMA measurements. In addition, the
extracellular potassium concentration [K+]e was recorded using ion-selective
microelectrodes. Before pilocarpine application, the ECS parameters were:  = 0.19 
0.01 and  = 1.58  0.01 (n = 7, mean  SEM). The volume fraction started to decrease
several minutes after the application of pilocarpine and reached a minimum value of
0.13  0.01 in 80–100 minutes. Approximately at 120 minutes  started to increase,
reaching 0.18  0.01 four hours after pilocarpine application. There were no significant
pilocarpine-evoked changes in tortuosity observed. However, ADCw was significantly
decreased 80 minutes after pilocarpine application (563  18 m2s-1, n = 5) compared to
controls (655  11 m2s-1, n = 5). By the end of the experiments, ADCw had returned to
control values. Decreases in  and ADCw were accompanied by an increase in
extracellular potassium concentration, indicating increased neuronal activity. Our results
show that pilocarpine-induced seizures result in long-lasting cell swelling.
Compensatory ECS shrinkage may contribute to an increase in the concentrations of
extracellular metabolites and neuroactive substances that can further aggravate
seizures. Recovery of ECS volume corresponds to the progressive reduction of
epileptiform activity 120 min after the administration of pilocarpine, probably attributable
to the depletion of cell energy reserves.
Supported by: AV0Z50390512 and 1M0538.
60
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Time course of water diffusivity in the rat brain after
global ischemia
I. VOŘÍŠEK1,2, H. NEPRAŠOVÁ1, M. ANDĚROVÁ1, D. JIRÁK3, M. HÁJEK3,
E. SYKOVÁ1,2
1
Institute of Experimental Medicine ASCR, Prague, Czech Republic,
Department of Neuroscience and Center for Cell Therapy and Tissue Repair, Charles
University, 2nd Medical Faculty, Prague, Czech Republic,
3
Institute for Clinical and Experimental Medicine, Prague, Czech Republic
2
Global cerebral ischemia is characterized by delayed neuronal loss and
reactive gliosis, especially in the CA1 region of the hippocampus. The aim of this study
was to evaluate the time course of changes in the apparent diffusion coefficient of water
(ADCW ), measured by diffusion-weighted magnetic resonance, in the CA1 region after
ischemia/reperfusion injury. We correlated the ADCW results with immunohistochemical
analysis of the damaged tissue, focusing on neuronal loss, reactive gliosis and the
expression of apoptotic markers. Global cerebral ischemia was induced in 2-month-old
male Wistar rats by a bilateral 15 min occlusion of the common carotid arteries
combined with hypoxic conditions (6%O2 / 94%N2). ADCW was measured in control rats,
after 1 hour, 6 hours, 1 day, 3 days, 7 days and 5 weeks of reperfusion. Sham operated
animals were measured 3 days after surgery. In the CA1 region global cerebral
ischemia led to an increase in ADCW (762 ± 5 m2s-1, n = 6) during the first hour of
reperfusion. No significant differences from control values (714 ± 7 m2s-1, n = 7) were
found at 6 or 24 hours after ischemia or in sham operated animals. Subsequently,
ADCW significantly increased to 756 ± 9 m2s-1 and 859 ± 12 m2s-1 (n = 6) after three
days and five weeks of reperfusion, respectively. Immunostaining revealed reactive
gliosis and neuronal loss in the CA1 region. The apoptotic markers casp-3 and PARP-1
were mostly activated in neurons in the CA1 region 6 hours after ischemia; after five
weeks they became detectable in astrocytes. The increase of ADC W at the begining of
reperfusion is probably caused by an increase in extracellular space volume after
ischemia, while the second peak in ADCW, three days after ischemia, coincides with
neuronal death in the CA1 region. The marked rise in ADCW five week after global
ischemia might reflect changes in astrocyte morphology and membrane properties.
Caspase-3 and PARP-1 immunoreactivity in this period implies either ischemic
preconditioning in astrocytes or ongoing programmed cell death in astrocytes
(apoptosis).
Supported by grants AVOZ50390512, MSMT LC554 and GACR 305/06/1316.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
61
Calbindin and S100 protein expression in the
developing inner ear of mice
D. BUCKIOVÁ, J. SYKA
Institute of Experimental Medicine, Academy of Sciences of the Czech Republic,
Prague
Calbindin D28K (CB) and S100 are calcium binding proteins known to be
expressed in the inner ear of adult mice. Limited information exists about their
occurrence during the inner ear development. This study demonstrates that the sites of
CB and S100 expression in the mouse inner ear during embryonic and early postnatal
development do not overlap and signal independent developmental patterns. The
expression patterns of CB and S100 were investigated in C3H mice by
immunohistochemistry, from embryonic day 11 (E11) to postnatal day 10 (P10). CB was
expressed in the otocyst and vestibulocochlear ganglion (VCG) from E11. In the
developing cochlea at E17, CB immunoreactivity clearly labeled the auditory ganglion,
the precursors of the outer and inner hair cells, and the stria vascularis. CB staining was
also present in the VCG and vestibular hair cells, including their nerve fibres. Two days
later, to this CB expression pattern was added the labeling of Kölliker´s organ. Early
postnatal CB expression encompassed spiral ganglion neurons, auditory hair cells, their
afferent nerve fibres and cells of the cochlear lateral wall. Cup-like calyceal terminals at
vestibular cells (type I) were CB immunostained as well.The first signs of S100
immunostaining of cochlear epithelial cells appeared at E14. At E17 S100 protein
showed a spatially restricted expression pattern in the cochlea. The stained area was
separated by a morphological furrow corresponding to the future site of the tunnel of
Corti. A few spiral ganglion nerve fibres labeled by S100 indicated that the developing
inner hair cells contain S100 as well. This finding and evidence that the pillar and
Deiters cells were immunostained at E19 supports the idea that S100 protein is involved
in pillar cell development. Immunostaining was also present in the vestibular cells and
their afferent fibres. Postnatally, S100 staining appeared in the inner hair cells, their
afferent nerve fibres, the outer hair and Deiters cells. Vestibular I and II hair cells in the
macula and crista ampularis and some vestibular neurons were labeled. In addition,
S100 immunostaining was present in the spiral limbus, the spiral prominence and the
intermediate cells of the stria vascularis. This study demonstrates Ca 2+ involvement in
several important steps of inner ear development in the mouse. Ca2+ ions participate in
cell migration and neuroblast differentiation. Also, the development of the organ of Corti
and the differentiation of auditory and vestibular sensory cells, including their inervation,
is influenced by Ca2+.
The study was supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 81134 and LC 554.
62
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Changes in GAD levels in the central auditory system
of two rat strains with aging
J. BURIANOVÁ, L. OUDA, O. PROFANT, J. SYKA
Institute of Experimental Medicine ASCR, Videnska 1083, 142 20 Prague, Czech
Republic
Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in
the mammalian neocortex and is critically involved in shaping neuronal responses in the
central auditory system. In the current study we evaluated age-related changes in the
levels of glutamate decarboxylase (GAD), the key enzyme in the formation of GABA, in
the inferior colliculus (IC) and auditory cortex (AC) of young and old animals of two rat
strains - Long Evans (LE), a strain with normal aging and preserved hearing function up
to late senescence, and Fischer 344 (F344), a fast aging strain with an early onset of
hearing impairment. The comparison was made between rats aged 3-5 months in both
strains and LE animals aged 27-33 months and F344 animals aged 20-24 months. GAD
is present in two isoforms, GAD65 and 67; immunohistochemistry was used to
investigate changes in GAD67 content and western blot technique to investigate
changes in GAD 65 and 67 content. GAD67-immunoreactive(-ir) neurons were present
in all subdivisions of the IC and in all layers of the auditory cortex in all examined
animals. Age-related changes in GAD67 immunoreactivity comprised a significant
decrease in the optical density of GAD67-ir neurons in the IC and AC of both old LE and
F344 rats. A decrease in the optical density was accompanied by a significant decrease
in the number of GAD67-ir neurons in the AC of both strains, especially in the superficial
layers (I-IV). In western blots, pronounced age-related decreases in the levels of
GAD65 and 67 in the IC and AC of both strains were found as well. In contrast, in the
visual cortices of both strains only a tendency towards a decrease in the levels of the
examined proteins was observed in old rats. In addition, western blots revealed a
striking difference in the amount of GAD65 and 67 between the IC and the cortical
regions. The densities of both isoforms were almost three times higher in the IC
compared to the auditory and visual cortices in young animals of both strains. With
either technique, no strain-specific changes were found with aging.
Supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 8113-4 and LC 554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
63
Aging influences parvalbumin expression in the
central auditory system of two rat strains
L. OUDA1, R. DRUGA2, J. SYKA1
1
Institute of Experimental Medicine ASCR, Videnska 1083, 142 20 Prague, Czech
Republic
2 nd
2 Medical Faculty, Charles University, V Uvalu 84, 150 06 Prague, Czech Republic
Changes in the levels of calcium binding proteins are known to occur in
different parts of the brain during aging. In our study we attempted to find out the effect
that aging has on the parvalbumin-expressing system of neurons in the higher parts of
the central auditory system. Age-related changes in parvalbumin immunoreactivity
were investigated in the inferior colliculus (IC), medial geniculate body (MGB) and
auditory cortex (AC) in two strains of rat, Long Evans (LE), a strain with normal aging
and preserved hearing function up to late senescence, and Fischer 344 (F344), a fast
aging strain with an early onset of hearing impairment. The comparison was made
between rats aged 3-5 months in both strains and LE animals aged 27-30 months and
F344 animals aged 20-22 months. In young animals of both strains, parvalbuminimmunoreactive(-ir) neurons were present in all subdivisions of the IC and in layers II-VI
of the auditory cortex. The number of PV-ir neurons in the MGB in all examined animals
was very low independently of the strain and age. In old LE rats the number of PV-ir
neurons was greater in the central nucleus of the IC; the optical density of their somas
was increased in comparison with young LE animals. In addition, the optical density of
PV-immunoreactive somas was also enhanced in the AC in this strain. In contrast, old
F344 rats showed a pronounced decline in the number of PV-ir neurons in the AC in
comparison with young F344 rats. In some parts of the AC of old F344 animals, almost
no PV-ir neurons were present at all. Changes in the AC in old Fischer 344 rats were
accompanied by a reduction in the cross-sectional areas of PV-ir neurons in the central
nucleus of the IC. The results clearly demonstrate that aging is associated with
significant changes in PV-immunoreactivity in the central auditory system of the rat and
that the changes are strain-dependent.
Supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 8113-4 and LC 554.
64
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Age-specific impairment of hearing function in the rat
N. RYBALKO, D.ŠUTA, J. PELÁNOVÁ, S. HAMSOVÁ, J. SYKA
Institute of Experimental Medicine, Academy of Sciences, Vídeňská 1083, 142 20
Prague 4, Czech Republic
The aim of our study was to assess age-related changes in the auditory
system of pigmented rats (Long Evans strain). These animals, with a relatively short lifespan in which age-specific cochlear impairment occurs later in life (Popelar et al.,
Neurobiology of Aging, 2006), are useful subjects for the investigation of presbycusis.
Auditory sensitivity (hearing threshold and gap detection threshold) and auditory
discrimination ability (frequency difference limen and gap duration difference limen)
were examined in young-adult (2-4 months) and old (28-34 months) rats using
behavioral and electrophysiological methods. The results show a small difference in
hearing thresholds between young-adult and old rats: the hearing thresholds increased
by 5-25 dB over the frequency range of 2-32 kHz during aging. Hearing thresholds
assessed by behavioral and electrophysiological methods in both age groups were
similar; the difference in thresholds did not exceed 5-10 dB. Frequency discrimination
slightly deteriorated during aging; age-related changes were revealed in some but not
all old rats. Old rats exhibited a considerable deficit in temporal resolution and in their
ability to discriminate the time parameters of acoustic stimuli. Gap detection thresholds
significantly increased from 1.8 ± 01 ms to 3.4 ± 0.5 ms during ageing. In all old rats the
values of gap duration different limens were larger than in young rats; Weber ratios for
the discrimination of gap duration increased two-fold with age. The results suggest that
aging in Long Evans rats is accompanied by deteriorated hearing function. The deficit in
the processing of temporal sound features present in old rats indicates an age-related
impairment, which may be localized in the central part of the auditory system.
Supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 8113-4 and LC 554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
65
Expression of cytoskeletal neurofilament protein in
the auditory cortex of rat
R. DRUGA1, J. SYKA2
1
Institute of Anatomy, 2nd Medical Faculty, Charles University in Prague
Institute of Experimental Medicine, Czech Academy of Sciences, Prague
2
Although according to the prevailing opinion the rat’s auditory cortex conform
to the basic mammalian plan. The growing body of data indicate significant differencies
between parcellation of the auditory cortex derived from the principal morphological
approach (packing density of neurons) on one side and from the electrophysiological
and functional metabolic techniques and data about the connections on the other side.
According the morphological criteria the auditory cortex is divided to three fields (Te 1,
Te 2, Te 3 ; Zilles and Wree, 1995) while the functional data and connectional pattern
offer parcellation to 4 – 6 cortical fields. We designed this study to analyze the
distributions of non-phosphorylated neurofilaments within rat temporal neocortex in
order to obtain additional data enabling the comparison with maps of the auditory cortex
based on connectivity and functional data. Selective neurofilament expression was
formerly used as a sensitive and specific method for detection of boundaries between
individual cortical fields and for the more detailed parcellation of the cortical areas.
Five young adult rats (strain Long Evans, age 4 – 5 months, weight 250 – 300
g) were used for this study. Animals were deeply anesthetized and perfused with 4 %
paraformaldehyde. Brains were postfixed, cryoprotected and 40 μm thick frozen frontal
sections were treated in a solution of SMI – 32 antibody (antibody against
nonphosphorylated epitopes in neurofilament subunits NF – M and NF – L; Sternberger
Monoclonals Inc, MD, USA) and further processed with ABC peroxidase method and
DAB as a chromogen.
Analysis of SMI – 32 immunoreactivity patterns revealed differencies in the
distribution of neurofilament protein-containing neurons across the temporal neocortex.
Striking differencies were evident between the primary auditory area (Te 1, Au 1) and
ventrally and dorsally situated associative auditory areas (Te A, Au V, and Au D;
Paxinos and Watson 2007). In the primary auditory area are evident two distinct layers
of strong immunopositivity in neurons and neuropil localized in the 3rd and 6th layer.
Additional less intensive immunostaining was evident in the 5th layer. Between the
primary auditory area and the ectorhinal cortex were discernible two areas where SMI –
32 immunostaining was weaker in all cortical layers and the positivity was evident only
in the 5th and 6th layers. The dorsal field AuD exhibited stronger immunostaining for
neurofilament protein only in the 3rd layer.
In summary the regional distribution of SMI – 32 immunoreactivity in the rat
temporal neocortex corresponds more with cortical areas as defined by functional
analysis than with the classical subdivision by Zilles and Wree (1995).
This study was supported by Grant of Grant Agency of the Czech Republic No
309/07/1336, Grant Agency of the Ministry of Health NR 8113 – 4 and Grant No LC 554.
66
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Functional and electrical membrane properties of
neurons in the auditory cortex in rats
O. PROFANT, K. LOMAKINA, R. TUREČEK, J. SYKA
Institute of Experimental Medicine ASCR, Prague, Czech Republic
The study focused on the functional and electrical membrane properties of
neurons in the auditory cortex (AC). In our previous study, five individual fields were
distinguished based on the neuronal response to simple acoustic stimuli such as broad
band noise (BBN) and pure tone bursts: primary auditory field (AI), anterior auditory field
(AAF), suprarhinal auditory field (SRAF), posterior auditory field (PAF) and belt area.
Neurons in the AI, AAF, SRAF and PAF typically responded to both pure tones and also
to BBN stimulation. In contrast, neurons located in the belt reacted only to BBN
stimulation. Individual fields were also characterized by latency, pattern, duration and
strength of the response. Auditory fields which differed most in the studied features
were the AI and belt area. The AI was the field with the shortest latency, the highest
response strength to BBN stimulation and the highest occurence of an onset response
pattern. On the other hand, the belt area had the longest latency and the lowest
response strength. Based on these findings, the AI and belt area were chosen for
further examination of the electrical membrane characteristics of pyramidal neurons in
layer V. A glass electrode was inserted into the AC in ketamine-xylazine anaesthetised,
30-35-day-old Wistar rats, and the approximate borders of the AI, AAF and belt area
were distingusihed on the basis of the neuronal response to BBN and pure tone bursts.
The neurons were then studied in supravital brain cortex slices. The current-clamp
mode of the patch-clamp technique was used to record the voltage responses of
neurons in brain cortex slices (300 – 400 μm thick) to both hyperpolarizing and
depolarizing current injections of variable amplitude. Two distinct classes of neurons,
formerly named as regularly spiking (RS) and fast spiking (FS), were found in both
areas of the auditory cortex (A1 and belt). The two populations clearly differed in their
steady state firing frequencies (34.3 ± 8.5 Hz evoked by a 0.3 nA current step in FS and
25.0 ± 6.2 Hz for RS) and in the length of the after hyperpolarization phase (AHP) of
postsynaptic action potentials (AHP peaked at 25.1 ± 6.1 ms after a spike in FS neurons
and 58.9 ± 14.4 ms in RS neurons). By comparing the passive membrane properties of
the A1 and belt neurons, we found that RS neurons from the belt showed a markedly
higher time membrane constant than their A1 counterparts (27.9 ± 6.5 ms vs. 17.5 ± 4.6
ms). This suggests a significantly lower resting membrane resistance of the A1 neurons.
Consistently, RS neurons from the belt showed a shift of the spike activation threshold
to more hyperpolarized potentials by 3.4 mV compared to the RS neurons from the A1.
Based on these findings, both extra- and intracellular features of neurons significantly
differ between the AI and belt area.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
67
Effect of noise exposure on the amplitudes of auditory
evoked responses in rats
J. GRÉCOVÁ, J. POPELÁŘ, J. SYKA
Institute of Experimental Medicine ASCR, Prague, Czech Republic
Noise exposure affects not only the peripheral, but also the central part of the
auditory system. Previously, we found enhanced cortical middle latency response
(MLR) amplitudes after noise exposure, but with large inter-individual variability. The
aim of this work was to record MLRs and auditory brainstem responses (ABRs) and to
analyze the relationship between hearing threshold shifts, changes of MLR and ABR
amplitudes and the slope of MLR and ABR amplitude-intensity functions (AIFs) after
noise exposure. MLRs and ABRs were recorded with electrodes implanted on the
surface of the rat brain; hearing thresholds were assessed on the basis of ABR
recordings. To produce various hearing treshold shifts, rats were exposed twice for one
hour to broad-band noise of 118 dB SPL (first exposure) and 122 dB SPL (second
exposure); the interval between the exposures was three weeks. One day after the first
exposure, hearing threshold shifts ranged between 5-45 dB at frequencies of 8-32 kHz.
Whereas maximal MLR amplitude enhancement reached up to 250% and the average
slope of MLR AIFs increased from the pre-exposure value of 2.75 ± 1.2 to 7.4 ± 3.7
postexposure, ABR AIFs after noise exposure were shifted in parallel to higher stimulus
intensities and ABR amplitudes were reduced. The almost full recovery of thresholds
and evoked response amplitudes to pre-exposure values was observed during two
weeks. The second noise exposure resulted in a more pronounced hearing threshold
shift of about 80 dB, but the maximal MLR amplitude enhancement was similar to that
measured after the first exposure, and the average slope of the MLR AIFs increased to
14.1 ± 3.7.
The second noise exposure produced a greater suppression of ABR
amplitudes than did the first exposure, and ABR AIFs were more shifted to higher
stimulus intensities while keeping their slope more or less unchanged. The results
demonstrate that noise exposure differentially affects ABR and MLR amplitudes:
whereas ABR AIFs after noise exposure were shifted in parallel to higher stimulus
intensities and ABR amplitudes were reduced and negatively correlated with threshold
shifts, MLR amplitudes were enhanced after noise exposure and MLR AIFs were
significantly steeper, correlating their slope with the threshold shift. Thus, changes in the
slope of MLR AIFs characterize more the effect of noise exposure on the central part of
the auditory system, whereas ABR suppression reflects mainly noise-induced changes
at the periphery.
Supported by grants AV0Z50390512, GACR 309/07/1336, IGA NR 8113-4 and LC 554.
68
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Spontaneous otoacoustic emissions in children and
adolescents - effect of cisplatin treatment
J. PELÁNOVÁ1,2, D. SUMERAUER3, M. ZÁPOTOCKÝ3, M. JILEK1, D. GROH2,
Z. KABELKA2, J. STARÝ3, J. SYKA1
1
Institute of the Experimental Medicine, Czech Academy of Science, Prague 4
Dept. of Pediatric ENT and
3
Dept. of Pediatric Hematology and Oncology, Faculty Hospital Motol and 2nd Medical
Faculty, Charles University, Prague 5
2
Spontaneous otoacoustic emissions (SOAEs) are spontaneous oscillatory
products of the outer hair cells recordable in the external acoustical meatus. They are
considered to represent a manifestation of the normal active feedback mechanism in
the cochlea. Previous studies have shown that typical SOAEs are characterized by one
or more peaks in the frequency spectrum with great stability in individual ears over time.
The aim of the study was to analyze the appearance and characteristics of SOAEs in a
group of 124 normal hearing children and adolescents aged from 6 to 25 years, to
correlate the findings with other audiological parameters measured in this group and to
compare them with findings in a group of 32 children treated with cisplatin as a cure for
several types of cancer.
In the normally hearing group, SOAEs were present in 70.1% of the
individuals in either one ear (55.4%) - with a higher occurrence in the right ear (55.4%) or in both ears (44.6%). They were present more frequently in girls (81.6%) than in boys
(58.1%). The frequency of the individual peaks of the SOAEs ranged between 0.5 and 6
kHz in all measured spectra, with a maximum in the speech-related range, especially
around 2 kHz. The presence of SOAEs was significantly correlated with larger
amplitudes of transiently evoked otoacoustic emissions (TEOAEs) and distortionproduct otoacoustic emissions (DPOAEs). The audiometric parameters were compared
in four age groups, each spanning five years of age. In the group of 21-25-year-olds,
individual hearing thresholds at 16 kHz were significantly better in individuals with
SOAEs than in those without SOAEs.
The results obtained in the normally hearing group were compared with the
results from the recording of SOAEs in children and adolescents treated with cisplatin in
a cumulative dose ranging between 200 – 1000 mg/m2 (469,6  158,71 mg/m2) for the
presence of osteosarcoma, chondrosarcoma, neuroblastoma or meduloblastoma. In the
cisplatin-treated group, SOAEs occurred in approximately 12% of ears only, with the
majority of the SOAE peaks found at frequencies ranging from 1 to 3 kHz. Their
incidence was very low even in children with relatively well preserved audiograms. The
mean number of SOAE peaks in the normally hearing group was 3.3 in one ear
whereas in the cisplatin treated group the number decreased to 1.4 in one ear.
In summary, the appearance of SOAEs may serve as an indicator of a healthy
ear with normally functioning outer hair cells whereas most pathological states results in
a decrease in the occurrence of SOAEs, up to their complete disappearance.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
69
Hearing Thresholds in the Extended Frequency Range
as a Function of Age and Sex
M. JILEK, J. SYKA
Institute of Experimental Medicine, Academy of Sciences of the Czech Republic
Videnska 1083, 142 20 Praha 4
If we want to compare the audiograms of persons of different age, we have to
normalize them. The normal thresholds of hearing by air conduction as a function of age
and sex are given by the ISO 7029 standard (ČSN EN ISO 7029). The threshold shift
depending on age is, in this standard, expressed as H = α (Y-18)2, where H is the
hearing threshold level in dB, Y is age in years and α is a coefficient that, in this
document, is given separately for men and women for each frequency used. However,
even the last version of this standard (2002) does not contain α for frequencies higher
than 8 kHz. Our aim was to determine α for frequencies of 10 kHz,
12.5 kHz and 16 kHz.
We measured the hearing thresholds of 102 (49 male and 53 female)
otologically normal persons over a frequency range of 125 Hz - 16 kHz with an Madsen
Orbiter 922 audiometer equipped with Sennheiser HDA 200 high frequency
headphones. The results of these measurements enabled us to plot a graph of hearing
levels vs. age. For frequencies of 10 kHz, 12.5 kHz and 16 kHz, we used curve fitting in
order to find the optimal values of coefficient α. However, the fitting was not precise for
high frequencies. With the linear approximation
H = a (Y–18) the fitting was more exact. The values of the coefficients α and a were
calculated separately for men and women.
Because the ISO 7029 standard does not cover frequencies higher than 8 kHz, our
results can be used in high frequency audiometry. Our data show, that for the highest
audible frequencies, the square-law is not valid and better fitting may be obtained with a
linear approximation.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Auditory cochlea-threedimensional MRI of the left and
right cochleo-vestibular organ
J. TICHÝ1, T. VITÁK2, O. DLOUHÁ3
1
Department of Neurology
Department of Radiology and
3
Department of Phoniatry
1th School of Medicine, Charles University Prague
2
The human body is asymmetrical and/or symmetrical. Some of body parts or
organs are in a mirror shape. The membraneous and osseous labyriths may be
examples of a such mirror shape arrangement.
The data about the left-right asymmetry could be found even in biology of
plants, in biochemistry as alpha- or beta- helices. About 90% of humans have clockwise hair whorl. The simillar percentage has been found in spiral shape in shell ulits.
Hypothesis
We were curious if such asymmetry of auditory cochlea could be found
different in left and right-handed human individuals.
A small group of left-handed individuals (-100%) has been compared with right-handed
persons (+100%) according The Edingurgh Inventory in this preliminary study.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
71
Adaptation of the olfactory receptor neuron of a moth
to the natural pheromone signal
L. KOŠŤÁL, P. LÁNSKÝ, JEAN-PIERRE ROSPARS
Fyziologicky ustav AVCR, UMR1272 UMPC-INRA-AgroParisTech
Studies on stimulus-response relationships were carried out on a model of
olfactory transduction in the pheromone receptor neuron of the male moth Antheraea
polyphemus. These neurons are capable of detecting rapid changes in stimulus
intensity encountered in natural pheromone odor plumes. Knowing the densities and
reaction rate constants of the perireceptor and receptor processes we predicted several
characteristics the pheromone stimulus should possess under the hypothesis that the
receptor neuron performs optimally, i.e. transfer as much information on the stimulus as
possible. Statistical characteristics of the stimulus were obtained and compared with the
experimental observations. The öoptimalö probability density function of the fluctuations
in the pheromone concentration was found to be exponential in good agreement with
experimental data. The predicted intermittency (12%) falls within the lower range of
experimentally observed values (10-40% depending on experimental conditions).
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Optimal odor intensity in simple olfactory neuronal
models
O. POKORA1, P. LÁNSKÝ2
1
Department of Mathematics and Statistics, Faculty of Science, Masaryk University,
Brno, Czech Republic
2
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech
Republic
Signal processing in olfactory systems is initiated by binding of odorant
molecules to receptor molecules embedded in the membranes of sensory neurons.
Three models of olfactory sensory neurons have been investigated. Their behavior is
described by stochastic processes of binding (and activation). The models assume that
the response, concentration of bound (activated) receptors, is determined by the signal,
which is fixed log-concentration of odorant in a perireceptor space. Dependency of the
mean response on the signal is realized through the input-output transfer function
(usually the logistic curve). How the concentration of bound (activated) receptors can
code the intensity of odorant is analyzed using the statistical properties of the steadystate responses.
Classical, deterministic, approach to the problem of finding a suitable signal is
based on the steepness of the input-output transfer function. For the logistic curve, the
best detectable signal is located at the inflexion point of the input-output function.
We use approach, which is based on stochastic variant of the law of mass
action as a neuronal model. We consider a model experiment in which a fixed odorant
concentration is applied several times and realizations of steady-state characteristics
are observed. The response is assumed to be a random variable with some probability
density function belonging to a parametric family with the signal as a parameter.
Different types of distributions of the response are considered. As a measure how well
the signal can be estimated from the response, the Fisher information and its lower
bound are used.
Results are compared with the classical approach to determine the coding
range via steepness of the input-output transfer function. The point in which the first
derivative of the input-output function is maximal coincides with the point of maxima of
the Fisher information in the simple models. The obtained results differ in the models
including the activation step.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
73
Rats do not learn to avoid a cued moving region in a
stationary environment but they learn to avoid the
cued region if it is stationary in a moving environment
K. BLAHNA1,2, B. OSECKÁ1, V. MAŇÁSKOVÁ1, D. KLEMENT1
1
Neurophysiology of Memory and Computational Neuroscience, Institute of Physiology,
Academy of Sciences of the Czech Republic,
2
Department of Zoology, Science faculty, Charles University
Rats easily learn to avoid place in their enviroment. Several aversive
behavioral tasks take advantage of it in order to test spatial memory and cognition.
However to-be-avoided place might not be only defined with respect to stationary
objects but also with respect to moving ones. In order to test whether rats can learn to
avoid a region bounded to a moving object we modified the behavioral task called AAPA
(Bureš et al, 1997; Fenton et al., 1998). Rats (n = 9) were trained on a stable arena to
avoided a region which rotated together with a distant object around the arena.
Performance of the rats did not improve during 7 days of training and it equaled to the
performance of the same subjects when the object was removed on the 8th day.
However the rats improved substantially on the 10th day when the arena rotated while
the region together with the distant object was stationary. A different group of rats (n =
7) was trained in the later version of the task (rotating arena, stationary to-be-avoided
region) from the very beginning. These rats improved substantially during the first four
days of the training. When these rats were tested on the stationary arena with the to-beavoided region rotating around the arena their performance was deteriorated. These
results indicates that the inertial information available to the subjects in the second
version of the task is crucial for the effective solution of the task.
This work was supported by grants MSMT CR 1M0519 and LC554.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Are inertial stimuli and/or motor skills sufficient for
successful navigation of rats in the AAPA task
(moving world)?
I. FAJNEROVÁ, J. KENNEY, D. KLEMENT
Dpt. of Neurophysiology of Memory and Computational Neuroscience, Institute of
Physiology, Academy of Sciences of the Czech Republic
Spatial cognition of rats is usually tested in stable environment. The recently
designed AAPA (Active Allothetic Place Avoidance) task is unique in this respect as it
requires the animals to distinguish between two subsets of orientation cues, the stable
extraarena cues and the continuously rotating intraarena cues. So far published
experiments always assumed that rats must use extraarena cues to perform well in the
task. As the speed of arena rotation is constant in time, it is however conceivable that
inertial stimuli and stereotypic motor behavior can substantially contribute to the solution
of the task. The goal of our study was to address this assumption by testing whether
rats are able to learn the task in a situation where extraarena cues are eliminated and
whether well trained rats are able to solve the task in this situation. Male Long Evans
rats (n=16) divided into two groups by 8 were trained in the AAPA task in a 5-day
training protocol for 5 weeks with or without extraarena cues available respectively. The
6th day of each week extraarena cues were eliminated for both groups and the rats’
strategies were tested. The rats previously trained in environment where extraarena
cues were not available did not learn the task, while those that had learned the task
using extraarena cues were after two weeks able to find an alternative strategy that was
however less efficient. We conclude that the rats’ performance in a standard 5-day
training protocol depends on the use of extraarena cues and that exposure to
extraarena cues is necessary for the rats to develop a successful strategy.
The work was supported by grants MSMT CR 1M0517 and LC554.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
75
Strategies used by rats during navigation toward a
visible moving target
D. KLEMENT1, K. BLAHNA1,2
1
Neurophysiology of Memory and Computational Neuroscience, Institute of Physiology,
Academy of Sciences of the Czech Republic
2
Department of Zoology, Science faculty, Charles University
Animals do not navigate to stationary goals only but also to moving ones.
Preys, predators and members of the same social group are examples of moving
objects which can be approached or avoided. In order to study strategies used by rats
to navigate toward moving objects we designed a novel spatial task in the water maze
apparatus. Rats (n = 7) were trained to navigate to a moving target in a circular
swimming pool (diameter = 191 cm). The target moved along the maze wall. Direction
of the target movement (clockwise, counter-clockwise), speed (slower than the rat,
faster than the rat) and starting position (northwest, northeast, south) changed between
trials in a pseudorandom manner but they remained constant within the trials. Well
trained rats changed their target-approaching strategy according to the speed of the
target. If it moved slower than the rats, the rats swam directly toward the target. If the
target moved faster than the rats, the rats swam along a straight line toward the place of
collision indicating that they were able to predict future positions of the target.
This work was supported by grants MSMT 1M0519 and LC554.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Role of posterior parietal cortex of the rat in two tasks
involving dynamic environment
J. SVOBODA1, P. TELENSKÝ1,2, J. BUREŠ1
1
Inst. of Physiology of Czech Academy of Sciences, Prague
Dept. of Zoology, Faculty of Science, Charles University, Prague
2
Most spatial tasks require animals to organize their behavior in relation to
stable environmental cues. However, cue manipulations such as rotation or transition
allow to assess their control exerted over behavioral processes and to examine
underlying brain mechanisms.
We used Long-Evans rats with lesion of posterior parietal cortex in two
behavioral tasks taking place in dynamic environment. Both of them were conducted on
elevated circular arena (d=80cm), in 20 min daily sessions. At first, the rats were trained
6 days in Robot Avoidance Task (RAT), in which the rat must keep safe distance at
least 25cm from a programmable robot to avoid a mild footshock. The robot was
programmed to move straight forward (15cm/s) until it hit the wall, then it waited for 15s,
turned 180 ± 0 to 90 degrees, and ran again. Two weeks after the first experiment, fooddeprived rats were trained to asymptotic performance in a modified version of Place
Avoidance (PA) task to search for randomly dispersed pellets while avoiding a small
sector on the arena. Since the sector is not directly perceivable rats can remember its
position either in the coordinate frame of the arena, or in the frame anchored to cues
outside the arena. By rotating the arena slowly while the shock is switched off
(extinction session), we may examine in which of these two frames the rats maintain
their avoidance. These rotation+extinction sessions were made twice (on day 8 and 15)
to see temporal consistency of the results.
Results showed that parietal rats (n=8) were slightly but not significantly
facilitated (p=0.10) in learning RAT when compared to controls (n=8). In addition, they
did not differ in locomotion or in thigmotaxis. Similarly, both groups learned the PA task
at the same rate. However, in both extinction sessions, parietal rats chose arena frame
more frequently than controls, which rather avoided in the room frame.
These results suggest that parietal rats may not have difficulties when
processing proximal cues. This is in contrast with data of other authors obtained in a
static environment task - water maze. In those experiments, lesions aimed to posterior
cortex disrupted navigation based on proximal cues, while navigation based on distal
cues left unaffected. We suggest that this discrepancy would be partly due to different
requirements of the tasks, since in water maze the target area is considerably small.
Supported by GACR grants 309/06/1231, 309/07/0341 and 206/05/H012, by MSMT
project 1M0517, and by AV0Z50110509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
77
Study of animal cognitive functions using an active
allothetic place avoidance task: assets, problems,
questions
A. STUCHLÍK, K. VALEŠ
Institute of Physiology, Academy of Sciences, Prague, Czech Republic
Spatial orientation belongs to the most intensively studied topics in cognitive
neuroscience. This type of behavior is often considered as a model of human higher
cognitive functions. Roughly ten years ago, a novel behavioral task, active allothetic
place avoidance (AAPA), was designed in our laboratory and our efforts to investigate
the task intimately date back to this time.
In this task, animals avoid an unmarked shock sector defined in a coordinate
frame of experimental room while moving over a rotating arena. It was established that
besides navigation with respect to a hidden place, the task requires cognitive
coordination, usually explained as an ability to separate spatial stimuli from the
environment into coherent representation of an arena and a room, and to select the
room frame as the only relevant one for efficient navigation.
We studied the effects of specific receptor antagonists on the behavior of
animals in this task and it was found that changes in spatial efficiency are often
accompanied by alterations in overall locomotor activity. In this regard, the task has an
advantage of simultaneous assessment of both place navigation and locomotor
behavior. The analysis of locomotion was found to be important for exclusion of a more
general impairment of animals after an experimental manipulation. The results suggest
that at least in some cases, the changed locomotion and decreased spatial efficiency
occur concurrently, but without a mutual causal relationship. The poster will sum up the
existing evidence about modulation of behavior in this spatial task.
Supported by grants GAČR 309/07/0341, IGA MZ ČR NR/9178-3 and MŠMT centers
1M0517 a LC554.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
All subtypes of mild cognitive impairment are
impaired in episodic-like memory
K. VLČEK, J. LACZO, O. VAJNEROVÁ, M. ORT, M. VYHNÁLEK, J. HORT
Department of Neurophysiology of Memory, Academy of Sciences, Czech Republic
Charles University, 2nd School of Medicine, Prague, Czech
Alzheimer’s disease (AD) is associated with a loss of episodic memory. It is
preceded by a stage of cognitive impairment without dementia, referred to as mild
cognitive impairment (MCI). Episodic-like memory concept was developed by Clayton
and Dickinson (1998) as the memory for information about ‘where’ a unique event or
episode took place, ‘what’ occurred during the episode, and ‘when’ the episode
happened. We developed non-verbal test of episodic-like memory for human presented
on computer. The test consists of a presentation and a testing phase. In the
presentation phase, the subject is shown a computer screen with several abstract
pictures on predefined places on the right part of the screen and an empty open chest
on the left. S/he is instructed to drag, using the computer mouse pointer, the pictures
from the predefined places in a given order slowly into the chest. The subjects should
memorize both the order and the position of each picture. After about 10 minutes break,
the subject should drag the pictures in the same order to the correct position.
Successively, memory for position and order of three, five and seven pictures was
tested. We evaluated separately the errors in giving order of the pictures, position of the
pictures and order of the predefined positions. Comparison was made among groups
diagnosed with non-amnestic, amnestic single domain and amnestic multidomain
subtypes of MCI, early stage of AD and a control group. The non-amnestic MCI subjects
were impaired in the order of the object, while the amnestic multidomain MCI subjects
were impaired in the object position. The amnestic multidomain and AD patients were
impaired in both. These results can be useful in predicting the outcome of different MCI
subtypes.
Supported by GACR grants 309/05/0693 and 309/06/1231, MSMT CR 1M0517 and
research project AV0Z50110509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
79
The effect of enforced physical activity and cerebellar
transplantation on spatial learning in Lurcher mutant
mice
J. CENDELÍN, I. KORELUSOVÁ, F. VOŽEH
Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University,
Czech Republic
Lurcher mutant mice represent a model of olivocerebellar degeneration. They
suffer from cerebellar ataxia and impaired spatial learning or orientation ability. The aim
of the work was to assess the effect of enforced physical activity and transplantation of
embryonic cerebellar tissue on spatial learning ability in young and aged Lurcher mutant
mice of the B6CBA strain.
Aged Lurcher mice were at least 60 days old (mean age 109 days) and young Lurchers
were 12-14 days old at the beginning of the experiment. Solid cerebellar grafts were
obtained from wild type mouse embryos and applied into the cerebella of the host mice.
To sham-operated control animals only the vehicle vas administered. One part of each
group of mice was then trained on the rotarod for 32 days over the course of 7 weeks.
The second part of mice of all groups remained inactive. Spatial learning was tested in
the Morris water maze from the 60th day after the surgery for 10 consecutive days. The
survival of the grafts was examined histologically. Spatial learning ability of both young
and aged Lurchers was also compared with wild type mice of the same age and strain,
which were not influenced by the training or transplantation.
The graft survived in 74 % of adult untrained mice, 67 % of adult trained,
88 % of young untrained and 100 % of young trained mice. Both young and aged
Lurchers showed significantly worse learning ability than wild type mice of the same
age. In wild type mice there were no differences in spatial learning ability between
young and older animals while aged Lurcher mutants achieved worse results than
young ones. Both the enforced training and transplantation led to improvement of
spatial learning ability in aged Lurcher mice. When not combined, the training was more
effective than the transplantation but trained mice with the graft showed similar results
as untrained mice with graft. In young Lurchers no effect of the training or
transplantation was observed.
In the contrary to wild type mice, in Lurchers spatial learning ability was
decreased by their higher age. Physical activity or transplantation helped older Lurchers
to compensate the age related deficit of spatial learning ability. This treatment improved
their learning ability almost to the level found in younger Lurchers, but not above it and
they remained still worse than wild type mice. Combination of both treatments did not
lead to any mutual enhancement of their effects. In young Lurchers, in which the spatial
learning test started at the age of 72-74 days, the treatment with the physical activity or
transplantation was completely ineffective.
The work was supported by the research project VZ MSM 021620816.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Retrospective longitudinal study of titres of specific
antibodies to β tubulin class III in patients with MS
and depression treated by glatimeracetate and SSRI
Š. CIHELKOVÁ1, M. MINÁRIKOVÁ1, M. HLADÍKOVÁ2, D. ŠKODA1, P. JINOCH3,
M. BOJAR1
1
Charles University Prague, 2nd Faculty of Medicine, Dpt. of Neurology, University
Hospital Motol, Prague, Czech Republic
2
Charles University Prague, 2nd Faculty of Medicine,
Objective
Hypothesis of the relationship between depression and dysfunction of the immune
system in MS patients is supported by psycho-neuroimmunological studies, clinical
experience and by neuroimaging methods which detected ceasing of the inflammatory
changes in MS patients treated by glatirameracetate and SSRI. IgM and IgG specific
antibodies to tubulin β class III (sabt) were found in samples from patients with NS
diseases causing axonal damage.
Methods
This retrospective longitudinal study was planned to compare the changes of titres of
IgM and IgG sabt in serum of MS patients treated by glatirameracetate and SSRI. All
patients were divided into 2 groups. Group A (n=21, glatirameracetate + SSRI), control
group (n=58, glatirameracetate). The titres of sabt were determined in all 79 patients in
the 6th month of the therapy, sabt were tested during the whole examination period
three times at least.
Results
The titres of sabt (IgG and IgM) decreased significantly from the start of glatimeracetate
therapy in group A+ control patients without a significant difference. A significant
decrease of IgM sabt titres was detected in the 6th month of glatimeracetate therapy in
depressive patients treated by SSRI (Group A) contrary to the patients untreated by
SSRI (Control group).
Conclusion
Decrease of IgM titres of specific serum antibodies to β tubulin class III found in patients
treated by glatimeracetate & SSRI supports the hypothesis of neuroprotective effect of
SSRI. A further research in MS patients treated with glatimeracetate and SSRI is
required.
This study was supported by a grant of IGA CR NR, 8114
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
81
Regulation of RGS3 function by 14-3-3 protein
E. BOUŘA1,2, T. OBŠIL1,2
1
Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles
University; 12843 Prague, Czech Republic
2
Institute of Physiology, Academy of Sciences of the Czech Republic; 14220 Prague,
Czech Republic
The regulator of G protein signaling (RGS) proteins serve as negative
regulators of G protein-mediated signal transduction. RGS proteins function both as
GTPase activating proteins and regulators of G protein-effector interactions. RGS
proteins act as GTPase activating proteins specific to Galpha subunit, and thus they
play a crucial role in the shutting off process of G protein-mediated cell responses. The
14-3-3 proteins are a family of regulatory proteins that play an important role in the
regulation of signal transduction, apoptosis, cell cycle control, and nutrient-sensing
pathways. It has been demonstrated that 14-3-3 proteins bind to other proteins in a
phosphorylation dependent manner. RGS3 protein is one of the RGS proteins recently
found to be 14-3-3 binding partners. The role of 14-3-3 protein in the regulation of RGS3
seems to be an inhibition of its GAP (GTPase activating protein) function on G protein
mediated signals. We have prepared RGS3/14-3-3 complex in vitro. Complex
stoichiometry and stability was investigated. Various methods of fluorescence
spectroscopy have been used to characterize conformational changes of RGS domain
induced by 14-3-3 protein. Crystal structure of RGS domain of RGS3 protein (pdb code
2OJ4) was solved and this structure has been used both to design and interpret
experiments based on tryptophan fluorescence.
Acknowledgment
This work was funded by Grants 204/06/0565 and 203/05/H001of the GACR, by Grant
KJB500110601 of the GAAV of the Czech Republic, by Research Project
MSM0021620835 and Center of Neurosciences LC554 of the MSMT of the Czech
Republic, and by Research Project AV0Z50110509 of the AVCR.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Does 14-3-3 Protein Affect Conformation of FoxO4
DNA-Binding Domain?
J. ŠILHAN1,2, E. BOUŘA1,2, P. VÁCHA1,2, P. HERMAN3, J. VEČER3, T. OBŠIL1,2
1
Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles
University; 12843 Prague, Czech Republic
2
Institute of Physiology, Academy of Sciences of the Czech Republic; 14220 Prague,
Czech Republic
3
Institute of Physics, Faculty of Mathematics and Physics, Charles University, Prague
12116, Czech Republic
14-3-3 proteins are abundant regulatory molecules expressed in all
eukaryotes. They bind to other proteins in a phosphorylation-dependent manner.
Through these interactions they are involved in signal transduction, metabolism control,
oncogenesis, or apoptosis. More then 300 different 14-3-3 binding partners were
identified up to date (e.g. FoxO, p21CIP1, BAD). Since the 14-3-3 protein molecule
seems to be very rigid, it was suggested that 14-3-3 protein functions as molecular
äanvilô that modulates both the structure and the function of the bound ligand.
We used fluorescence spectroscopy to investigate whether the 14-3-3 protein changes
conformation of DNA Binding Domain (DBD) of transcription factor FOXO4. FOXO4
(AFX) belongs to a family of forkhead transcription factors family and regulates life
span, response to stress and apoptosis. AKT/PKB-induced phosphorylation of FOXO4
at Thr28 and Ser198 generates two 14-3-3 protein binding sites. The 14-3-3/FOXO4
complex is subsequently rapidly relocated from the nucleus to the cytoplasm probably
as a result of the 14-3-3 protein-mediated hindrance of FOXO4 nuclear localization
sequence (NLS). It is also known than 14-3-3 protein inhibits DNA-binding potential of
FOXO4 through still not fully understood mechanism.
Main goal of this study was to investigate whether the 14-3-3 protein binding
affects the conformation of FOXO4 DBD. AKT/PKB-phosphorylation sites Thr28 and
Ser193 were mutated to generate versions of FOXO4 containing only one
phosphorylation site. Time-resolved tryptophan fluorescence intensity and anisotropy
decays of single and doubly phosphorylated FOXO4 mutants were measured to
investigate the 14-3-3 protein-induced changes of FOXO4 DBD structure and mobility.
Our data indicate that 14-3-3 protein binding does not induce any significant structural
changes in FOXO4-DBD. Thus the 14-3-3 protein-induced inhibition of FOXO4 DNA
binding potential results from other processes, e.g. the masking of DNA binding
interface.
ACKNOWLEDGEMENT
This work was funded by Grant 204/06/0565 of the Grant Agency of the Czech
Republic, by Grant KJB500110601 of the Grant Agency of the Academy of Sciences of
the Czech Republic, by Research Project MSM0021620835 and Centre of
Neurosciences LC554 of the Ministry of Education, Youth, and Sports of the Czech
Republic, and by Research Project AV0Z50110509 of the Academy of Sciences of the
Czech Republic.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
83
Determinants of calmodulin binding site on the C-tail
of TRPC6 channel
E. FRIEDLOVÁ1, L. GRYCOVÁ1, Z. LÁNSKÝ1, M. ŠULC2, J. TEISINGER1
1
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech
Republic
2
Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech
Republic
Transient receptor potential channel TRPC6 is a non-selective calcium
permeable cation channel expressed in many cell types, including sensory receptor
cells. TRPC6 consists of four subunits with six membrane-spanning domains and
intracellular N- and C-terminal. Calmodulin (CaM) takes part in the calcium dependent
regulation of many proteins, including ion channels. There was identified one CaM
binding site on the C-tail of TRPC6. The aim of this study is to map in detail C-terminal
region of mouse TRPC6 that is capable of interacting with CaM using in-vitro binding
assays. The part of sequence of the C-tail (amino acids 801-878) was subcloned into
pET15b or pET42b expression vectors and used as a template for site directed
mutagenesis. There were performed mutations of several amino acid residues that
could potentionally distrupt CaM binding. These residues were chosen on the basis of
three-dimensional computer model. All fusion proteins were expressed in E. coli Rosetta
(DE3) and purified using nickel-chelating sepharose. The homogeneity of the purified
recombinant proteins was confirmed by SDSľPAGE electrophoresis and mass
spectrometry. The ability of binding of the protein (amino acids 801-878) and its mutants
to CaM was tested by fluorescent anisotropy measurements using CaM Alexa Fluor 488
fluorescent probe. Our results show that amino acids R852, Y854, K856, M858, K859,
R860, L861, K863, R864 and L867 participate in CaM binding on C-termini of TRPC6.
This work was supported by Grant GAAV IAA600110701, GACR 303/07/0915, project
(No. H148), Centre of Neurosciences No. LC554 MSMT CR, Research project No.
AVOZ 50110509
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
ATP binding studies on the C - termimus TRPV1
L. GRYCOVA1, Z. LÁNSKÝ1, E. FRIEDLOVÁ1, M. KUBALA2, J. TEISINGER1
1
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech
Republic
2
Department of Experimental Physics, Faculty of Science, Palacky University, Olomouc,
Czech Republic
Transient receptor potential channel vanilloid receptor subunit 1 (TRPV1) is a
non-selective cation channel, with the relative preference for Ca2+ and Mg2+, responsible
for a heat and chemical – evoked pain response. TRPV1, together with more than 30
homologous channels, belonging to the TRP channels family that could be divided into
seven subfamilies. Although ATP by itself doesn’t have the function of direct activator,
intracellular ATP increases TRPV1 currents by direct interaction with the nucleotidebinding domains, so called Walker A and Walker B motifs, that are homologous to other
ATP binding proteins. On the basis of this similarity and using the structure of Fragile
histidine triad protein (FHIT) a comparative computer model of the C- terminus was
created and molecules of ligands were docked. The main aim of our study was the
estimation of the role of single amino acids those create the ATP binding domain and
the confirmation of the ability to bind ATP to isolated C-tail TRPV1. In order to do that,
the set of single amino acids inside the walker motif A, were selected and using PCR
replaced by alanine. Protein was expressed in bacteria E. coli strain BL21. To avoid
impurities, two steps of purification protocols were performed. Consequently
fluorescence ATP binding studies were undertaken, namely TNP-ATP competitive
binding assay, steady-state and time resolved measurement of FITC labeled samples
and quenching of FITC fluorescence. Our experimentally gained results are in
accordance with our comparative computer model and confirm the ability of isolated CT
TRPV1 to bind TNP-ATP and ATP. Mutation of K735 caused the complete inability to
bind ATP to the isolated C-terminus TRPV1. K735 could be pointed out as a crucial
residue for ATP binding.
ACKNOWLEDGEMENT
This work was supported by Grant GAAV IAA600110701, GACR 303/07/0915, project
(No. H148), Centre of Neurosciences No. LC554 MSMT CR, Research project No.
AVOZ 50110509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
85
Possible involvement of ryanodine receptor-controlled
calcium release in sensitization of GnRH-stimulated
IP3 receptor in melatonin-sensitive neonatal
gonadotrophs of the rat
A. BALÍK, I. SVOBODOVÁ, H. ZEMKOVÁ
Dep. of Cellular and Molecular Neuroendocrinology, Inst. of Physiology, AS CR, Prague
Ca2+ mobilization plays an important role in pituitary function by stimulating
Ca2+-dependent synthesis and release of pituitary hormones. In addition to inositol1,4,5-trisphosphate (IP3) mediated Ca2+ mobilization, Ca2+ release from ryanodine (Ry)sensitive pools and Ca2+-influx through voltage-dependent Ca2+ channels, storeoperated channels and TRP channels have been suggested to be important in pituitary
Ca2+-signaling. The function of IP3 and Ca2+-conducting channels is relatively well
documented. However, the molecular identity of IP3 receptors (IP3R) and function of
ryanodine receptors (RyR) are still elusive. We have previously shown that GnRHstimulated Ca2+-signaling in a subpopulation of neonatal gonadotrophs is sensitive to
melatonin, a hormone secreted by pineal gland. Removal of extracellular calcium delays
the onset of agonist-stimulated Ca2+ oscillations similarly as melatonin, indicating that
extracellular Ca2+ influx could play an important role in melatonin inhibition of neonatal
pituitary gland function. Here we hypothesized that Ca2+-stimulated RyR is important for
sensitization of IP3R in neonatal gonadotrophs and contributes to melatonin inhibitory
effect on calcium signaling. Using PCR and patch-clamp techniques, functional
expression of RyRs and IP3 channels was determined in mixed population of anterior
pituitary cells. The mRNA transcripts for RyR type 1, 2, and 3 subunits were identified in
6-days old rats. The specificity of primers was further confirmed by the sequence
analysis of PCR products. In patch-clamp experiments on identified neonatal pituitary
gonadotrophs, GnRH application induced oscillatory hyperpolarizing current mediated
by activation of Ca2+-activated K+ channels, that reflected oscillatory InsP3 mediated
Ca2+ release. In melatonin-sensitive gonadotrophs, the onset of GnRH-induced current
oscillations were delayed by ryanodine and shortened by applications of caffeine (0.5
mM). Neonatal pituitary expressed also all types of IP3R, the IP3R1, IP3R2 and IP3R3.
In identified gonadotorphs, intracellular introduction of IP3 stimulated Ca2+-oscillations
that were insensitive to Ry application. Our findings suggest that, in addition to InsP3
mediated Ca2+ release, Ca2+ release from ryanodine-sensitive stores mediated by
RyR1-3 might contribute to Ca2+ mobilization in neonatal pituitary gland. The expression
of functional RyR could represent important components of Ca2+ signaling in neonatal
pituitary which could explain its specific inhibition by melatonin.
86
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Identification of Transmembrane Residues
Contributing to Channel Gating and Interaction with
Ivermectin at Rat Purinergic P2X4 Receptor
H. ZEMKOVÁ1, I. JELÍNKOVÁ1, V. VÁVRA1, M. JINDŘICHOVÁ1, T. OBŠIL2,
H.W. ZEMKOVÁ2,3, S.S. STOJILKOVIC3
1
Department of Cellular and Molecular Neuroendocrinology, Institute of Physiology
ASCR, Prague
2
Department of Protein Structure, Institute of Physiology ASCR, Prague
3
Section on Cellular Signaling, Development Neuroscience Program, NICHD, NIH,
Bethesda, USA
Ivermectin (IVM) is a member of class of lipophilic compounds known as
avermectins, that are used as an antiparasitic agent in human and veterinary medicine.
The therapeutic effects of IVM is mediated by its interaction with glutamate-gated
chloride channels expressed by parasite, leading to muscle paralysis and starvation. In
addition to glutamate-gated chloride channels, IVM modulates function of several other
ligand-gated channels, including GABAA receptors, recombinant glycine-activated
chloride channels, and neuronal α7nicotinic receptors. At purinergic P2X receptors
(P2XRs), a family of ligand-gated ion channels activated by binding of extracellular ATP,
IVM specifically enhances the P2X4R-channel function by interacting with the open
conformation state of the channel. IVM increases both the sensitivity of receptor to ATP
and the current amplitude in response to supramaximal agonist concentrations. It also
greatly prolongs the deactivation of current after agonist washout. We have previously
shown that IVM actions are independent of ectodomain structure of P2X4R. In this
study we used cysteine scanning mutagenesis of both transmembrane domains (TM) of
the rat P2X4R and examined effects of mutations on ATP potency, peak amplitude of
currents in response to supramaximal agonist concentrations, and receptor deactivation
in the absence and presence of IVM. The receptor function was unchanged in mutants
of 28 residues, and among them the IVM effects were altered at Gln36, Leu40, Val43,
Val47, Trp50, Asn338, Gly342, Leu346, Ala349, and Ile356 mutants. The substitutionsensitive Gly29, Arg33, and Cys353 mutants could also be considered as IVM-sensitive
hits. The pattern of these 13 residues was consistent with helical topology of both TMs,
with every third or fourth amino acid affected by substitution. These predominantly
hydrophobic-nonpolar residues are also present in the IVM-sensitive Schistosoma
mansoni P2X subunit. They lie on the same side of their helices and could face lipids in
the open conformation state and provide the binding pocket for IVM. In contrast, the
IVM-independent hits Met31, Tyr42, Gly45, Trp46, Val49, Gly340, Leu343, Ala344,
Gly347, Thr350, Asp354, and Val357 map on the opposite side of their helices,
probably facing the pore of receptor and playing important roles in gating. These results
for the first time identified residues of the potential importance for P2X4R channel gating
and interaction with IVM.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
87
Disruption of the plasma membrane structure by
depletion of cholesterol impairs effectiveness of TRH
receptor-mediated signal transduction via Gq/11-alpha
protein
P. OSTAŠOV, J. NOVOTNÝ, L. BOUŘOVÁ, L. HEJNOVA, P. SVOBODA
Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083,
142 20 Prague 4, Czech Republic
According to the raft hypothesis, sphingolipid-cholesterol microdomains are
involved in a number of signaling processes in the plasma membrane. Here we aimed
to evaluate the presumed role of these structures in signal transduction mediated by
thyrotropin-releasing hormone (TRH) receptors and their cognate Gq/11-alpha proteins.
These experiments were conducted in HEK293 cells transfected to express high levels
of TRH receptors and G11-alpha protein (clone E2M11). We monitored distribution of
TRH receptors and Gq/11-alpha proteins, as well as a functional status of the whole
signaling system. Our analyses indicated that disruption of plasma membrane
microdomains by cholesterol depletion (through beta-cyclodextrin treatment) did not
markedly influence binding parameters of TRH receptors, but altered efficacy of signal
transduction. The functional coupling between TRH receptor and Gq/11-alpha was
assessed by agonist-stimulated GTPgammaS binding and results of these
measurements pointed out to significantly lower potency of TRH to mediate G-protein
activation in samples prepared from cholesterol-depleted cells; there was a shift in
sensitivity by one order of magnitude to the right. A similar marked shift to the right in
the sensitivity to stimulation with TRH was observed in our experiments dealing with
determination of the hormone-induced Ca2+ response. Moreover, cholesterol depletion
prolonged lag phases and somewhat reduced maximal TRH-induced Ca2+ responses.
Our additional investigations performed by fluorescence confocal microscopy indicated
that treatment with beta-cyclodextrin also affected the pattern of Gq/11-alpha
distribution in the plasma membrane of E2M11 cells. Subcellular fractionation studies
indicated that membrane domains/rafts were degraded by cholesterol depletion in intact
cells. Collectively, results of our present study suggest that the intact structure of
plasma membranes is intact structure of plasma membranes is necessary for an
optimum signal transduction initiated by TRH receptors and mediated by Gq/11-alpha
proteins.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Calcium responses to thyrotropin-releasing hormone
and angiotensin II. The role of plasma membrane
integrity and effect of G11-alpha protein
overexpression on homologous and heterologous
desensitization
J. NOVOTNÝ, P. OSTAŠOV, J. KRUŠEK, D. DURCHÁNKOVA, P. SVOBODA
Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083,
142 00 Prague, Czech Republic
The molecular mechanisms involved in thyrotropin-releasing hormone (TRH)
and angiotensin II (ANG II) receptor-mediated signaling are still not understood in detail.
Here we analyzed hormone-induced Ca2+ responses and the process of desensitization
in HEK-293 cells, which express endogenous ANG II receptors. These cells were
transfected to express also high levels of TRH receptors (clone E2) or both TRH
receptors and G11a protein (clone E2M11). We observed that the characteristics of
Ca2+ responses, as well as the process of desensitization of hormone response, both
were strongly dependent on the receptor number and G11-alpha protein level. Whereas
treatment of E2 cells with TRH or ANG II led to significant desensitization of Ca 2+
responses to subsequent stimulation, these responses were not desensitized in E2M11
cells expressing high amounts of G11-alpha. Importantly, the process of desensitization
and recovery of the Ca2+ response was strongly dependent on temperature. Besides
that, addition of THR to both cell lines elicited a clear heterologous desensitization of
the Ca2+ response to ANG II. On the other hand, ANG II did not affect subsequent
response to TRH. In addition, ANG II-mediated signal transduction was strongly
dependent on plasma membrane integrity, but signaling through TRH receptors was
relatively slightly modified by cholesterol depletion. It might be concluded that the level
of expression of G-protein-coupled receptors and their cognate G-proteins strongly
influences not only the magnitude of cellular response but also the process of
desensitization and resilience of transmembrane signaling mediated by these receptors
to changes in the plasma membrane structure.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
89
Delayed effects of xanomeline on evoked ACh release
from rat brain slices
E. MACHOVÁ1, J. JAKUBÍK1, E. E. EL-FAKAHANY2, V.DOLEŽAL1
1
Inst. Physiol. CAS, Prague, Czech Republic
Univ. Minnesota Med. Sch., Minneapolis, USA
2
Xanomeline binds to the orthosteric site of all muscarinic receptor subtypes
with high affinity but in short-term assays selectively stimulates only M1 and M4
receptors. We observed previously that at all receptor subtypes xanomeline also
interacts with another distinct site where it binds in a wash-resistant manner. This
unusual type of binding caused delayed persistent stimulation of GTP-γ 35S binding at
the M1 receptor and with lower efficacy but similar affinity also at the M2 receptor (1). It
also causes durable antagonism of M5 receptor activation (2). To further investigate the
functional outcome of wash-resistantly bound xanomeline we tested assumed direct and
delayed effects of xanomeline on electrically-evoked ACh release from rat brain slices
that is autoinhibited by presynaptic M2 and M4 receptors in cortical and striatal slices,
respectively. Slices were loaded with tritiated choline to label acetylcholine and then
exposed for 15 minutes to xanomeline either 1 hour before or during measurement of
electricaly-evoked ACh release. Xanomeline (10 µM) had no direct effect on ACh
release in either cortical or striatal slices. In contrast, wash-resistantly bound
xanomeline (15-minutes preincubation with 1, 10 or 100 µM xanomeline followed by 1
hour washing before stimulation) concentration-dependently decreased ACh release
from both cortical and striatal slices. Xanomeline delayed effects were not additive to
the decrease of ACh release caused by the agonist carbachol. Furthermore,
xanomeline did not prevent inhibitory effect of carbachol when present together during
stimulation. Wash-resistant effects of xanomeline were fully (1 and 10 µM) or partially
(100 µM) reversed by 1 µM N-methylscopolamine, a muscarinic antagonist. However,
delayed inhibitory effects of xanomeline were not prevented by either presence of Nmethylscopolamine during xanomeline treatment or irreversible inactivation of the
orthosteric binding site by propylbenzilylcholine mustard prior to xanomeline treatment
in cortical slices. These data demonstrate that xanomeline functions as wash-resistant
M2 or M4 agonist and that the orthosteric binding site is not necessary for creation of
wash-resistant binding. On the other hand, blocking of the orthosteric site can at least
partially prevent agonistic effects of wash-resistantly bound xanomeline. Together,
these findings strongly indicate that the complicated pharmacological profile of
xanomeline action may be also due to not yet well characterized effects of washresistant xanomeline at all subtypes of muscarinic receptors thus far tested.
1. Jakubík et al.: Mol.Pharmacol. 70, 656-666, 2006; 2. Grant and El-Fakahany,
J.P.E.T. 315, 313-319,2005
Supported by project AV0Z50110509, grants GACR305/05/0452 and LC554.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Cholesterol differentially influences G-protein
signalling activated by the muscarinic M2 receptor
P.MICHAL, E.E.EL-FAKAHANY, V.DOLEŽAL
Inst. Physiol. CAS, Prague, Czech Republic
Univ. Minnesota Med. Sch., Minneapolis, U.S.A.
The muscarinic acetylcholine M2 receptor that was originally identified as the
predominant muscarinic receptor subtype in the heart is also widely distributed in the
central nervous system. Its signal transduction is effected by both the βγ dimer of
heterotrimeric G-protein that activates potassium or inhibits calcium conductance and
the α subunit that preferentially inhibits cAMP synthesis. However, we demonstrated
that M2 muscrinic receptors expressed in CHO cells (CHO-M2) directly activate
signalling pathways of all three major subclasses of G-proteins, i.e. preferred Gi/o
subclass and at concentrations higher than needed for standard inhibition of forskolinstimulated cAMP synthesis also Gs and Gq/11 subclasses to cause stimulation of cAMP
synthesis and accumulation of inositolphosphates (IP), respectively (1-3). In the present
experiments we investigated influence of membrane cholesterol content on activation of
signalling pathways of these three G-protein subclasses in CHO-M2 cells by carbachol,
a non-hydrolysable acetylcholine analogue. Treatment of cells with methyl-βcyclodextrin decreased cell and membrane cholesterol content by 74% and 39%,
respectively, and incubation in the presence of cholesterol-saturated methyl-βcyclodextrin increased cholesterol content by 169% and 137%, respectively. The
decrease in cholesterol was accompanied by an increase of plasma membrane
muscarinic receptor density measured in saturation binding experiments with the
tritiated non-permeable antagonist 3H-N-methylscopolamine by 63% in intact cells
whereas the increase in cholesterol had no significant effect. Cholesterol depletion
increased efficacy of carbachol in inhibiting forskolin-stimulated cAMP synthesis by 35%
(Gi/o) and in stimulating cAMP synthesis by 69% (Gs) but decreased its efficacy in
stimulating IP accumulation by 35% (Gq/11). Cholesterol enrichment significantly
reduced cAMP synthesis inhibition (by 23%) but had no effect on stimulation of cAMP
synthesis or IP accumulation. Cholesterol depletion significantly increased the potency
of carbachol on the IP response (decrease of EC50 from 83 to 49 μM) but had no
influence on its potency in stimulating or inhibiting cAMP synthesis. These findings may
be relevant to the impairment of brain cholinergic transmission and cognitive functions
in neurodegenerative diseases linked to abnormalities of cholesterol metabolism like
Alzheimer´s disease.
1. Michal P. et al.: J.Pharmacol.Exp.Ther. 320, 607-614, 2007. 2. Jakubík et al.:
Mol.Pharmacol. 70, 656-666, 2006. 3. Michal P. et al.: Br.J.Pharmacol.:132, 1217-28,
2001.
Supported by project AV0Z50110509, grants GACR305/05/P209, GACR305/05/0452,
LC554 and NIH NS25743
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
91
Looking for fluorescent probes for allosteric binding sites
at muscarinic receptores: Unusual, but not exclusive,
mechanism of interactions of tacrine at muscarinic
receptors
J. PROŠKA, M. DVOŘÁK
Department of Physical Electronics, Faculty of Nuclear Sciences and Physical
Engineering, Czech Technical University in Prague, Prague, Czech Republic.
It has been observed repeatedly1[1,2], that the inhibitor of cholinesterases
tacrine (1,2,3,4-tetrahydroacridin-9-amine) inhibits the binding of orthosteric muscarinic
ligands to muscarinic receptors with unusually steep binding curves (high Hill slopes
about value 1.5). Definite explanation of this phenomenon is not available. A
mechanistical model has been proposed according to which tacrine binds to the
orthosteric site and to the allosteric site simultaneously with homotropic positive
cooperativity [3]. At the same time, the binding of tacrine to the allosteric site has a
negative efect on the binding of the commonly used radiolabelled muscarinic ligands
([3H]N-methylscopolamine, or [3H]quinuclidinyl benzilate) to the classical site. Another
hypothesis suggests that tacrine binds to two spatially separated allosteric sites on
muscarinic receptor with positive cooperativity or its binding to the common allosteric
site modulates receptor-receptor interactions [4]. We have discovered recently that
structurally closely related compounds 7-methoxytacrine, acridin-9-amine, and
proflavine (acridine-3,6-amine) also yield characteristically steep binding curves while
quinacrine
(6-chloro-9-([4-diethylamino]-1-methylbutyl)amino-2-methoxyacridine)
behaves like a competitor and displaces the orthosteric ligand [3H]Nmethylscopolamine yielding the standard curves with Hill slope close to 1. These
experimental findings are rather surprising. First, tacrine has been synthesized as a
three-dimensionally voluminous analogue of acridin-9-amine in order to demonstrate
that the complete planar acridine nucleus is required for antibacterial activity.
Nevertheless, their effects at muscarinic receptors are almost identical. On the other
side, allosteric modulators proflavine and acridin-9-amine, together with 'orthosteric'
competitor quinacrine belong to the same category of compounds which possess the
very special mechanisms of action: intercalation, stacking and self-aggregation [5]. We
hypothesize that the bulky substitution at position 9 on basic acridine skeleton sterically
hinders the simultaneous binding quinacrine into orthosteric and allosteric binding sites
while the molecules of tacrine, or 7-methoxytacrine, respectively, can stack themselves,
as do molecules of proflavine, or acridin-9-amine, inside the receptor pocket.
[1] Potter LT et al (1989). Mol. Pharmacol. 35, 652-660
[2] Mohr K & Trankle C (1994). Pharmacol. Toxicol. 75, 391-394
[3] Proska J & Tucek S, (1995). Proceedings of the Ninth International Symposium on Cholinergic
Mechanisms, Mainz, Germany, 38
[4] Trankle C et al (2003). Mol. Pharmacol. 64, 180-190
[5] Berman HM & Young PR (1981). Ann.Rev. Biophys. Bioeng. 10, 87-114
Work was partially supported by Research Project MSM6840770022 (Ministry of Education, Youth
and Sports)
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
M1 receptors participate in the nonquantal
acetylcholine regulation via feedback NO action
AI MALOMOUZH, MR MUKHTAROV, EE NIKOLSKY, F. VYSKOČIL
Fyziologický ústav AVČR a Přírodovědecká fakulta UK Praha, ČR a Lékařská universita
Kazaň, Rusko
Nitric oxide (NO), previously demonstrated to participate in the regulation of
the resting membrane potential in skeletal muscles via muscarinic receptors, also
regulates non-quantal acetylcholine (ACh) secretion from rat motor nerve endings(1).
The muscarinic agonists oxotremorine and muscarine lowered the H-effect and the M1
antagonist pirenzepine prevented this effect. M-agonist ABET, which is more selective
for M2 receptors than for M1 receptors and DAMP, a specific antagonist of M3
cholinergic receptors had no significant effect on the H-effect. The oxotremorineinduced decrease in the H-effect was calcium and calmodulin-dependent. The decrease
was negated when either NO synthase was inhibited by L-NAME or soluble guanylyl
cyclase was inhibited by ODQ. The target of muscle-derived NO is apparently nerve
terminal guanylyl cyclase, because exogenous hemoglobin, acting as an NO scavenger,
prevented the oxotremorine-induced drop in the H-effect. Oxotremorine and non-quantal
ACh selectively inhibit the non-quantal secretion of ACh from motor terminals acting on
post-synaptic M1 receptors coupled to Ca2+ channels in the sarcolemma to induce
sarcoplasmic Ca2+ dependent synthesis and the release of NO. It seems that a
substantial part of the H-effect can be physiologically regulated by this negative
feedback loop, i.e., by NO from muscle fiber and take place during synapse fomation,
maintenance and degradation; there is apparently also Ca2+ and calmodulin-dependent
regulation of ACh non-quantal release in the nerve terminal itself, as calmidazolium
inhibition of the calmodulin led to a doubling of the resting H-effect.
Grants RSSF,GAAVA5011411,AV025011922 and LN544.
(1)Malomouzh et al., J. Neurochem.102:2110-7(2007)
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
93
Photoperiodic entrainment of the circadian molecular
clock in the mice SCN
S. SOSNIYENKO1, R. HUT2, K. MATĚJŮ1, M. SLÁDEK1, H. ILLNEROVÁ1, A.
SUMOVÁ1
1
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague
Department of Chronobiology, University of Groningen, the Netherlands
2
The circadian rhythms are controlled by clock located in two suprachiasmatic
nuclei (SCN) of the hypothalamus. The basic molecular core clock mechanism
responsible for generation of the SCN rhythmicity became partly elucidated with cloning
of mammalian clock genes. The underlying mechanism is based on interlocked
feedback loops between transcription of clock genes and translation of their protein
products. The SCN rhythmicity and molecular core clockwork are affected by duration of
daylength, i.e., photoperiod that changes with the season in the temperate zones.
The aim of this study was to characterize the effect of the rectangular (abrupt
light on/off transition) and twilight (gradual light on/off transition) photoperiod on the
molecular time keeping system within the mice SCN. Mice were maintained under a
long (18h of light and 6h of darkness, LD 18:6) or a short (6h of light and 18h of
darkness, LD 6:18) photoperiod with rectangular or twilight light/dark transition. Daily
locomotor activity was monitored. On the day of the experiment, mice were released
into constant darkness and sacrificed every 2h throughout the whole circadian cycle.
Daily profiles of mRNA of clock gene, namely Per1, Per2, Cry1, Cry2, Bmal1, Clock,
and immediate-early gene c-fos, as well as of proteins, namely PER1, PER2 and cFOS, were determined in the SCN by in situ hybridization and immunohistochemistry
respectively. The photoperiod affected phase, waveform, and amplitude of the rhythmic
profiles of gene and protein expression as well as phase relationship between the
profiles.
The data indicate that the complex molecular clockwork in the mice SCN is
photoperiod modulated and hence may differ according to the season of the year. The
modulation is also is significant under nature-like conditions of photoperiod with twilight.
94
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Subunit composition of hippocampal NMDA receptor
in heuristic (animal) model of schizophrenia
F. ŠŤASTNÝ1,2, J. KLASCHKA3, I. KOZMÍKOVÁ4, H. TEJKALOVÁ1, M. VRAJOVÁ1
1
Prague Psychiatric Center
Institute of Physiology
3
Institute of Computer Science and
4
Institute of Molecular Genetics, Academy of Science, Prague, Czech Republic
2
The pathophysiology of schizophrenia is poorly understood but is likely to
involve alterations in excitatory glutamatergic signaling that may be related to
dysregulation in the expression of the N-methyl-D-aspartate receptor (NMDA-R)
subunits in cortical-subcortical brain areas. Heterogeneity of the postmortem findings is
an occasion for validation of the NMDA-R hypofunction hypothesis using heuristic
(neurodevelopmental) animal models of schizophrenia. As prenatal inflammation
belongs to risk factors in the etiopathogenesis of schizophrenia, we used an animal
model of schizophrenia based on the intraventricular (i.c.v) infusion of quinolinic acid
(QUIN), a potentially excitotoxic metabolite of tryptophan, levels of which are increased
during brain inflammations. The QUIN infusion on postnatal day 12 (PND 12) resulted in
a reduction of NMDA-sensitive [3H]glutamate binding to the hippocampal membranes of
rat males on PND 50 [1]. Further analysis of the decreased NMDA-R density revealed
changes in the laterality and protein expression of main subunits forming the receptor
NR1/NR2 tetramer. We showed that there is an asymmetrical expression of protein for
hippocampal NR1 subunit in intact/controls which disappeared in rats with model
psychosis representing a significant decrease in the subunit NR1 protein in the left
hippocampus. The hippocampal NR2 subunit were well-detectable in Western blots
except the NR2C protein. The subunit NR2A protein exhibited insignificant elevation in
the left hippocampus, but was significantly less expressed in the hippocampi of
neonatally QUIN-treated rats. In contrast, the NR2B subunit was more expressed in the
right hippocampus of naïve rats and highly significant decreases were found in both
hippocampi of rats with model psychosis. Upon neonatal QUIN treatment the
expression of NR2D subunit decreased by one/third in the both rat hippocampi.
Interestingly, the asymmetry of the NR2D expression was reversed in the neonatally
QUIN-treated animals with a higher NR2D density in the left hippocampus. This is the
first report demonstrating right/left asymmetry in the protein expression of NR1 and
NR2D subunits of NMDA receptors in the rat hippocampus. Based on our data we
propose that the alteration of the left/right asymmetry of NMDA receptor expression may
play a role in schizophrenia.
Supported by grants IGA MHCR NR8797 and CNS 1M0517
References
[1] F. Stastny, H. Tejkalova, I. Skuba, V.J. Balcar, M. Kaiser, Y. Yoneda, Quinolinic acid, N-methylD-aspartate receptor and schizophrenia: testing an integrative theory. In: Y. Yoneda (Ed.), Amino
Acid Signaling 04. Research Signpost, 2005, pp. 67-83.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
95
Acute and subchronic administration of quinolinic
acid and psychotic-like behaviour in
neurodevelopmental model of schizophrenia
H. TEJKALOVÁ1, J. KLASCHKA2, F. ŠŤASTNÝ1,3
1
Prague Psychiatric Centre affiliated with Charles University - 3rd Medical Faculty
Institute of Computer Science and
3
Institute of Physiology, Academy of Science, Czech Republic
2
Schizophrenia (SCZ) is considered to be a serious mental disease with
compromise working capacity, social interactions and family life. Its etiology is still
largely unknown but increasing evidence suggests that SCZ results from an interaction
between genetic background and early environmental factors. The adverse
environmental factors, infectious agents and consequently released substances like
cytokines, are involved in abnormal brain development resulting from the affected
neuronal proliferation, migration and formation of synaptic connections. The constructed
animal model was based on the simulation of pro-inflammatory processes as one of
environmental factors asserting in early periods of the brain development. Previous
results have suggested that neonatal exposures of rats to quinolinic acid, a cytokine-like
product of activated microglia/macrophages (QUIN), alters developmental processes
and can induce behavioural changes comparable to schizophrenia. Male Wistar rat
pups were daily injected with QUIN in a dose of 1 mg and/or 10 mg/kg intraperitoneally
(i.p.) between postnatal day 4 and 8 (PND 4-8) whereas controls were injected with
saline only; intact (naïve) pups were without manipulation. On PND 50 the prepulse
inhibition (PPI) of acoustic startle (ASR), a measure of sensorimotor gating, was carried
out to study the mechanisms acting as a filter of environmental stimuli. Clinical findings
have reported that the PPI is regularly disrupted in schizophrenic patients and,
therefore, it was used to investigative the psychopathology of SCZ. The PPI was
measured, after a 5-min habituation, in pseudo-randomly arranged 50 trials with the
intensity of 3, 5 and 10 dB above “white” noise (70 dB). Results showed that QUIN
administered in early neonatal period (PND 4-8) did not change basal startle amplitudes
(ASR) when injected systematically at daily doses of 1 and 10 mg/kg i.p., respectively.
Also any significant alteration of PPI levels was observed in 50-day-old rats. However,
impairment of PPI was found after the intracerebroventricular (i.c.v.) infusion of QUIN
application as it was shown in previous experiments. We conclude that the systemic
administration of this cytokine-like compound is not sufficient to affect negatively the
development of sensorimotor gating owing to (1) low doses of QUIN used and/or to (2)
the blood-brain barrier functioning. In contrast, the i.c.v. administration of QUIN
documents an existing vulnerability of the immature rat brain to infectious stimuli as a
risk factor for manifestation psychotic-like behaviour.
Supported by research project MHCR 0PCP2005.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Protein expression of NMDA-NR1 subunit and
acoustic startle in genetic (animal) model of
schizophrenia
M. VRAJOVÁ1,2, H. TEJKALOVÁ1,2, J. KLASCHKA4, F. ŠŤASTNÝ1,2,3
1
Centre of Neuropsychiatric Studies in Prague, Czech Republic
Prague Psychiatric Centre – 3rd School of Medicine in Prague, Czech Republic
3
Institute of Physiology,
4
Institute of Computer Science, Academy of Science of the Czech Republic
2
Decreased expression of ubiquitous NMDA-NR1 subunit in some
schizophrenic brain regions has been related to several single nucleotide
polymorphisms (SNP) in the subunit gene GRIN1 [1]. Also the neurodevelopmental
(animal) model of schizophrenia-like behaviour based on the neonatal treatment of 12day-old rat pups with quinolinic acid (QUIN; 250 nmol/0.25 μL 0.9% NaCl into each
lateral cerebral ventricle), exhibited a decrease in the hippocampal subunit NR1 protein
together with an impairment in the sensorimotor gating (a deficit in the prepulse
inhibition of startle reaction) accompanying schizophrenia-spectrum disorders [2].
However, the changed levels of the subunit NR1 protein went together with modified
expression of NR2 subunits, it was impossible to reveal a direct relationship between
the decreased NR1 expression and changed prepulse inhibition (PPI) of the acoustic
startle (ASR). Therefore, we tried to decrease selectively the expression of NR1 subunit
using a single dose (5 nmol/2.5 μL H2O) of (a) antisense oligodeoxynucleotide (aODN;
the 18-mer of NR1 sequence corresponding to bases 4-21 [3]), (b) sense
oligodeoxynucleotide (sODN) specific for NR1 subunit and/or (c) distilled H2O infused
into ventral hippocampi of 50-day-old rat males. Twenty-four hours later, we determined
a statistically significant decrease of the NR1 protein levels in right hippocampi (cca
20 %), but PPI of the ASR remained unchanged. At the next stage of NR1 subunit
suppression we infused the aODN, sODN (20 nmol/24 h) and/or H2O for 7 days with
the Alzet mini-osmotic pumps (Model 2001, rate 1 μL/h). The aODN-induced decrease
in the NR1 protein expression was similar to its acute application, but the PPI was not
changed. Our findings can be interpreted as follows: (1) the aODN-induced decreases
in the NR1 protein expression are not sufficient to change PPI values and/or (2) the
changed NR1 expression is not directly related to PPI deficits.
Supported by Research Project CNS 1M0517
References
[1] Begni, S., Moraschi, S., Bignotti, S., Fumagalli, F., et al., Association between G1001C
polymorphism in the GRIN1 gene promoter region and schizophrenia. Biol Psychiatry 53 (2003) 617619.
[2] Šťastný F., Kozmiková, I., Klaschka, J., Peková, S. et al., Expression of NR1 subunit of NMDA
receptor in animal model of schizophrenia. Psychiatrie 10 (2006) 12-15.
[3] Murata M., Suzuki M., Tanaka K., Tajiri K. et al., N-Methyl-D-aspartate-R1 receptor antisense
oligodeoxynucleotide modulates pre- and postsynaptic expression of D2 dopamine receptors in the
rat. Neurosci Lett, 335 (2002) 9-12.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
97
Lateralization of 17beta-hydroxysteroid
dehydrogenase type 10 in hippocampi of demented
and psychotic patiens
Z. KRIŠTOFÍKOVÁ, D. ŘÍPOVÁ, P. HOVORKOVÁ, A. HOŘÍNEK1, E. MAJER2,
J. ŘÍČNÝ
Prague Psychiatric Center, Ústavní 91, 181 03 Prague 8, Czech Republic
1
1st Medical Faculty, Charles University, Albertov 4, 128 00 Prague 2, Czech Republic
2
Patol s.r.o., Ústavní 91, 181 03 Prague 8, Czech Republic
Multifunctional mitochondrial enzyme 17beta-hydroxysteroid dehydrogenase
type 10 can play a role in the development of Alzheimer disease via its high-affinity
binding to amyloid beta peptides. In the brains of Alzheimer disease patients, enzyme
overexpression has been found. We evaluated specificity of alterations in enzyme
mRNA levels in human autoptic right and left hippocampi. We observed marked
right/left laterality in nondemented nonpsychotic controls and in people with multi-infarct
dementia. In Alzheimer disease and schizophrenia, however, shifts to left/right
asymmetry were found and the changes were associated with the increase especially in
the dominant left hemisphere. Our results are in agreement with the studies reporting
the involvement of mitochondria in modulation of intracellular levels of sex steroids and
in behavioral laterality. Moreover, our experiments support the studies reporting
overexpression of some mitochondrial enzymes and increased vulnerability of the
dominant left hemisphere in Alzheimer disease. However, the similar -although smaller changes observed in the hippocampi of patients with schizophrenia are surprising and
suggest that overexpression of enzyme should not be associated only with the
intracellular amyloid beta peptide pathway. We suppose that the enzyme influences the
development of sex-dependent brain asymmetry and that its levels e.g. in CSF could be
used as a biomarker to distinguish Alzheimer disease from multi-infarct dementia.
Nevertheless, a direct estimation of laterality in activity/enzyme expression should be
performed in future. Another subtypes of vascular dementia and another dementias
remain to be elucidated
Supported by MŠMT (1M0517), IGA MZČR (NR/9322-3) and MZČR (MZOPCP2005)
projects.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Absorption of high-frequency electromagnetic
radiation by the mouse brain; theoretical model and
real experiment
J. BARCAL1, V. ŽALUD1, F. VOŽEH1, J. VRBA2
1
Charles University in Prague, Faculty of Medicine Pilsen, Department of
Pathophysiology; Czech Republic
2
Czech Technical University in Prague, Faculty of Electrical Engineering, Department of
Electromagnetic Field; Czech Republic
High frequency electromagnetic field (HF EMF) became a common part of our
environment because it is produced by many artificial sources as radars, transmitters
and especially cellular (mobile) phones. In the presenting study we demonstrate a
possible methods for theoretical and real measurement of HF EMF absorption using
900 and 1800 MHz microwave source.
Experimental animals were exposed to HF EMF with frequency of 900 and
1800 MHz. Output power of the HF EMF generator after amplifying was aproximately 10
W or 1 W respectively. Mice were placed into a plastic box just before the orifice of the
waveguide. Control mice were kept in analogous conditions without the HF EMF. In the
first phase model experiments arranged for SAR (Specific Absorption Rate) detection
were performed. The value shows a absorption dose of radiation in the animal tissue. In
the distance 0.3 m from the orifice it is practically impossible to measure SAR directly
and only an estimation (from the gradient of the field) suggests the whole-body
exposure which correspond to the triple power of classical GSM.
In the second part a computerized modeling of electromagnetic field
absorption in the animal body was created. To estimate SAR in experimental animals
we have done basic 3D calculation of electromagnetic energy distribution in a simplified
dielectric model of an adult mouse. The model consists of a homogenous lossy
dielectric material mimicking muscle tissue and it has cylindric shape (radius 3 cm and
high 9 cm terminated to cone) with dielectric properties er = 54, conductivity s = 0.8
S/m, density r = 1000 kg/m 3. The calculations were done with the aid of 3D
electromagnetic field simulator SEMCAD which used FDTD (Finite Different Time
Domain). The method is based on the fact that original continuous function is replaced
by the set of discrete function‘s values. Maxwell‘s equations are discretized using a 2 nd
order finite-difference approximation both in space and in time in an equidistantly
spaced mesh. Several simulations for different positions of mice were done.
Calculations of SAR performed in connection with the simulation of absorption
electromagnetic energy by experimental animals using the arteficial dielectric model
showed the dependence of the absorption on the real topical position of the mouse
against the waveguide and was in the range of 0.05 to 1.44 mW/g.
This work was supported by the Research Program Project No. MSM 021620816 and
COST EU - Action B.30 (NEREPLAS)
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
99
Calretinin-contaning neurons in normal and epileptic
human temporal neocortex
F. BAŘINKA¹, R. DRUGA¹, J. ZÁMEČNÍK²
¹Department of Anatomy, 2nd Medical School, Charles University in Prague, Czech
Republic
²Department of Pathology and Molecular Medicine, 2nd Medical School, Charles
University in Prague, Czech Republic
The calcium binding protein Calretinin (CR) labels a specific interneuronal
subpopulation in cerebral neocortex. CR immunoreactive (CR-ir) neurons typically
innervate dendritic shafts and to a lesser degree dendritic spines of pyramidal neurons.
At least in superficial cortical layers, they also innervate and thus inhibit the other
interneuronal subpopulations and provide so the desinhibition of pyramidal neurons.
The aim of this study was to evaluate the distribution of CR-ir neurons in the
normal human temporal neocortex.
Human brain tissues included in the study were obtained shortly post mortem
during autopsies of 6 patients, who died due to diseases non-affecting the nervous
system. Temporal pole and neighbouring parts of superior, middle and inferior temporal
gyri were examined. 4 μm thick paraffin-embedded sections, monoclonal anti-CR
antibodies, biotin streptavidin detection system and DAB for chromogenic development
were used.
Two-dimensional counting method was used, the counts of immunopositive
neurons were expressed as cell density per μm 2. The highest average cell density was
found in supragranular layers- I. 27 neurons/μm2, II. 138 neurons/μm 2, III. 59
neurons/μm2. Density in IV. layer was 20 neurons/μm 2. In infragranular layers, the cell
density was markedly lower – 4 neurons/μm2 in V.+VI. layers. Occasionally, few CR-ir
neurons were located in white matter. CR immunoreactivity of neuropil was highest in I.
cortical layer, high in II. and III. layers and low in V. and VI. layers. The majority of CRimmunoreactive neurons exhibited bipolar and bitufted somatodendritic morphology.
The results are in accordance with similar, previously published studies on human as
well as on animal experimental material. The results of this study will be used as a
control in the study of CR-immunoreactive neurons in temporal cortex in patients
suffering from farmacoresistant epilepsy. After preliminary evaluation of material
acquired from patients with various types of temporal lobe epilepsy, it seems that there
is no significant change of CR-ir neurons density comparing to healthy controls.
This work was supported by Grant GA UK no. 7354/2007.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Changes in the permeability of blood brain barrier:
Cortical photothrombosis and epileptic seizure
induced by flurothyl inhalation
D. KRÝSL, L. TŮMA, J. POKORNÝ, J. MAREŠ
ÚNPKF, 3. LF UK, Prague.
We evaluated local and remote changes of blood brain barrier (BBB)
permeability in the model of cortical photothrombosis (PT) and tested the influence of
the choice of anaesthetic agent on our results. Also, we evaluated overall changes in
BBB permeability after flurothyl (FT) induced seizure.
Male Wistar rats were used for all the experiments (w = 200-220g). We have
described the PT model in our previous publications. After i.v. application of Rose
Bengal (RB), three stereotactically defined spots on the scull overlaying the left
sensorimotor cortex were irradiated by a laser beam. Each spot was irradiated for 6
minutes. The animals were divided in two subgroups: in the first group, the rats were
anaesthetised with pentobarbital (PB; N=3), in the latter, ketamine/xylazine was used
instead (K/X; N=4). Animals of the control group received saline in place of RB (N=4).
In another group of animals (N=4), generalized epileptic seizure was induced
by FT inhalation. FT was applied at a constant rate on a filtration paper located at the
top of an airtight chamber, in which the rats were placed. At seizure onset, the air in the
chamber was rapidly exchanged.
Immediately before irradiation in the PT model and before FT inhalation in the
FT seizure model, the rats received i.v. Evans Blue (EB; 0.04 g/kg/2ml). In case of BBB
disruption, the EB-albumin complex escapes from the blood vessels, and causes a blue
stain of the adjacent nervous tissue. 24 hours after experimental manipulations, the
brains of all animals were fixated, sectioned and evaluated with a fluorescence
microscope.
24 hours after PT, all experimental animals showed large ischemic lesions
located in the left sensorimotor cortex. An area of tissue showing BBB disruption
surrounded the lesions. In this area, brightly red cells accumulating EB (EB+) were
observed. The lesions were larger in the K/X group (mean lesion volume - MLV = 16.26
mm3), but the area of BBB disruption was relatively small (mean volume of tissue
showing BBB disruption - MPV = 2.62 mm3). In the PB group, the lesion core was
smaller (MLV = 15.11 mm3), however, a large area of BBB disruption (MPV = 9.46 mm 3)
surrounded the lesion. Moreover, in the PB group, EB+ cells were also observed in
remote areas (incl. cerebellum).
Epileptic seizure induced by FT inhalation did not lead to lasting significant
changes in the BBB permeability.
In the PT model, both the volume of the lesion core and the volume of tissue
with BBB impairment can be influenced by the choice of anaesthesia. In addition, in the
PB group, remote neuronal accumulation of EB was observed (to our knowledge, we
are the first to report such results). Isolated FT seizure does not lead to lasting changes
of BBB permeability.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
101
Preconditioning effect of normobaric intermittent
hypoxia on behavioral consequences of chemically
induced seizures in rats
K. DEYKUN, M. POMETLOVÁ, J. MAREŠ
Ústav normální, patologické a klinické fyziologie, 3. lékařská fakulta Univerzity Karlovy v
Praze
Flurothyl vapors evoke tonic-clonic epileptic seizures in rats causing
worsening of learning in water maze, despite absence of morphological changes. We
presume involvement of free radical release in this. Earlier, we described protective
effect of hypobaric hypoxia induced prior flurothyl seizures (FS). Intermittent normobaric
hypoxia (INH), as occurs in obstructive sleep apnea, causes cognitive changes due to
extreme production of free radicals. Present study was aimed to investigate whether
INH would exhibit cross-preconditioning on FS in Wistar rats. To reveal cognitive
changes we use Morris water maze (MWM). Three experiments were performed. First
group was exposed to INH and flurothyl 3 days afterwards; second – to hypoxia alone,
third – to flurothyl alone. Results were compared with controls (MWM tested only). INH
was conducted in chamber (4L) in which oxygen concentrations were cycled between
21 and 8% every 30s during one hour. INH, FS alone or combination of both caused
increase in latency and distance moved in WMW, in comparison to control animals.
However, there was significant improvement of performance of animals preconditioned
by INH in contrast to FS group. Thus on one hand, these findings confirm our
hypothesis that INH has protective preconditioning effect, an increase of further insult
tolerance. On the other, despite this effect it still causes some worsening of learning and
memory comparing to our previous results with hypobaric hypoxia.
Support: Research goal MSM 0021620816
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
The Effect of ET-1 on the Excitability of the Rat
Cortical and Hippocampal Slices in Vitro
R. KONOPKOVÁ, I. VILAGI, S. BORBELY, H. KUBOVÁ, J. OTÁHAL
Institute of Physiology, ASCR, Prague, Czech Republic; Physiology and Neurobiology,
ELTE University, Budapest, Hungary
In the mammalian CNS, endothelin (ET-1) potent vasoconstrictor is produced
in neurons, endothelium and in the glial cells. It has been suggested that ET-1 may
induce a wide range of physiological actions in CNS. In our lab, we apply direct injection
of ET-1 into brain parenchyma as a model of focal ischemia in rats in vivo. Intracerebral
application of ET1 produces seizures and starts epileptogenesis (Mateffyova, EJN
2006). Our aim was to conclude if epileptogenesis occurs due to the ischemia or if ET-1
itself also has an impact on excitability of the tissue. Experiments were performed in 15
adult, male Wistar rats (120-180 g). Animals were decapitated under deep anaesthesia,
the brain cut in coronal and hippocampal (400 μm) slices. The slices were incubated in
the incubation chamber containing buffered ACSF, ET-1 in concentration 20µM was
added in ET-1 group. After one hour the slice was placed into interface recording
chamber (perfusion 3ml/min) where the slices were maintained at 33 ± 1 °C in
humidified, carbogenated (95% O2, 5% CO2) gas atmosphere. Glass microcapillary
extracellular recording electrode (5-10 MΩ) filled with 1 M NaCl was positioned in the
third layer of the somatosensory cortex of the cortical slice and in the stratum radiatum
in the hippocampal slice, bipolar tungsten stimulating electrode was placed below the
recording electrodes at the border of the white and gray matter in cortex and in the CA1
pyramidal cell layer in hippocampus. 10min after replacement of the slice into the
recording chamber we determined the stimulus threshold. Every ten minutes up to 70
minute I/O curve was obtained by gradually increasing stimulus intensity in the range of
T-4T in cortical slice and in the range of T-2.5T in hippocampus. Slope of the I/O curve
was calculated from linear regression coefficient. For statistical comparison of
thresholds and slopes t-test or ANOVA were used where appropriate. Cortical results:
The evoked responses in both cortical groups have shown the same shape. The slope
of the I/O curve does not significantly changed between measurements in both groups
(contr P=0.9; ET-1 P=0.99). The slope of the control group was 26.1±0.97° and
29.93±3.5° in ET-1 group. There was no statistically significant difference between the
groups (P = 0.62). Hippocampal results: The pop spikes have had the same shape in
both groups. The slope of the controls was 48.69±3.3° and 48.15±3.1° of ET1group.There was no statistically significant difference between the groups (P=0,907).
In conclusion, our data shows that ET-1 does not directly influence excitatibility of both
the rat cortical and hippocampal slices.
The project was supported by grant of the ASCR no. 1QS501210509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
103
Alteration of regulation of the regional cerebral blood
flow in chronic epileptic rats
J. OTÁHAL, G. TSENOV, P. MRÁZOVÁ, H. KUBOVÁ
Institute of Physiology, Czech Academy of Sciences, Czech Republic
Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic
Regulation of regional cerebral blood flow (rCBF) is important function of the
nervous tissue which has to be finally ôtuned upö to cover metabolic demands of the
tissue. However, in epileptic patients is relative hypoperfusion observed after the
epileptic seizure as revealed by postictal SPECT. Thus it suggests that regulation of the
rCBF might be altered. Thus we performed in vivo cortical measurement of blood flow in
chronic epileptic rats. Broadly accepted model of the temporal lobe epilepsy (LiClpilocarpine) was used (Otahal et al, Epilepsia, 2005) Briefly, at postanatal day 12 (P12)
males (n=9) of wistar rats were intaperitonealy injected with pilocarpine (40mg/kg) to
produce status epilepticus. Peripheral cholinergic side effect of pilocarpine was
minimized by pretreatment with scopolamine (1mg/kg, 1hr before). Day before were
animals injected with LiCl (127mg/kg, i.p.) to decrease the dose of pilocarpine. Two
hours after the SE developed it was stopped by application of the paraldehyde
(0.3ml/kg, i.p.). Controls (n=10) obtained all treatment except pilocarpine. In part of
experimental animals spontaneous epilepsy developed during 3 weeks. Part of the
animals from both groups was EEG monitored for 72hours to confirm presence of
spontaneous seizures. To assess rCBF rats were 3-6months after initial SE
anesthetized with urethane (1g/kg, i.p.) Laser doppler probe was placed over the
senzorimotor cortex. Two epidural stimulation silver electrodes were implanted
contralaterally. EEG recording electrodes were implanted over the both hemispheres.
The temperature of the animal was kept constant. Spontaneously breathing animals
underwent series of stimulation to assess I/O relation. Changes of the rCBF were
monitored during transcalosal stimulation (20Hz, 10s) with increasing currents (1-8mA).
All results are expressed as means±S.E.M. For statistic comparison t-test was used
where appropriate and ANCOVA was used to compare linear regression of I/O curves.
EEG monitoring revealed presence of spontaneous seizures in 25% of animals. The
stimulation of the contralateral senzorimotor cortex produced significant increase of the
cerebral blood flow in both groups. The shape was monophasic in both groups with
latency of the maxima 9.8±1.2s in controls and 9.8±0.8s (P=0.72) experimental group
respectively. The rCBF fall back to zero in 36±3.5s and 29±3.4s (P=0.13) respectively.
When comparing slopes of the I/O curve ANCOVA reveals significant increase in
pilocarpine group (P<0.05). In conclusion, our data suggest that in chronic epileptic rats
is regulation of the rCBF significantly altered.
The project was supported by grant of the ASCR no. 1QS501210509.
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6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Effects of metabotropic glutamate receptor 5
antagonist MPEP on learning in developing rats
A. MIKULECKÁ, P. MAREŠ
Institute of Physiology, Academy of Science of the Czech Republic, Prague, Czech
Republic
Highly selective mGluR5 antagonist MPEP was used to elucidate the role of
mGluR5 subtype of metabotropic glutamate receptors in certain forms of learning and
memory. This subtype of receptors is distributed in various brain regions such as
hippocampus, amygdala and cortex. In our laboratory, MPEP was found to exhibit
anticonvulsant action in adult and immature rats without inducing side effects in motor
performance, therefore we studied its effects on learning in the immature rats.
The experiments were performed in 12-, 18-, and 25-day-old Wistar albino
rats. Experimental animals received i.p. 20 or 40 mg/kg of MPEP, controls received
saline and were tested for on a simple olfactory learning in the homing response test:
Instead of true homing, a single pup was placed in an empty cage connected with the
home cage occupied by littermates. A number of twelve trials with a 60s inter-trial
intervals was chosen for 12-day-old rats. Ten trials were chosen for 18- and 25-day-old
rats with a 180-s and 300-s inter-trial intervals respectively. A correct homing response
was considered if the pup was able to reach the home cage within the 60s interval.
Twelve trials for 12-, and 10 trials for 18- and 25-day-old were used. The following
criteria were evaluated: the ratio of correct homing responses to the total number of
trials, the mean latency to homing and occurrence of five consecutive correct homing
responses.
Either dose of MPEP impaired the homing response in 12-day-old rats in all
measured behavioral parameters if compared with the controls. Higher MPEP dose
exhibited a similar effect in 18-day-old rats whereas lower dose did not compromise
homing. In 25-day-old rats, neither of MPEP doses affected the homing response.
In conclusion, MPEP affected the homing response of developing rats in a
dose- and age- dependent manner. The inability of 12- and 18-day-old pups, treated
with MPEP, to return into their home cage suggests an impairment of their olfactory
spatial learning.
This study was supported by a grant No. 305/06/1188 of the Grant Agency of the Czech
Republic and by a research project AV0Z 50110509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
105
Does paraldehyde treatment participate in short-term
effects of status epilepticus in immature rats?
G. TSENOV, H. KUBOVÁ, P. MAREŠ
Department of Developmental Epileptology, Institute of Physiology, Academy of
Sciences of the Czech Republic, Prague, Czech Republic
Purpose
To study participation of paraldehyde and/or lithium-chloride administration in
short-time consequences of status epilepticus (SE) in immature rats.
Methods
SE was elicited by pilocarpine (40 mg/kg i.p.) in 12-day-old rats pretreated 24
hours before with LiCl (3 meq/kg, i.p.). Paraldehyde (0.3 ml/kg i.p.) was administered
after two hours of continuous SE. Some drugs were replaced by saline in other
experimental groups so that drugs they received were only LiCl, only paraldehyde or a
combination of LiCl and paraldehyde. Controls received three saline injections. Cortical
stimulation and registration electrodes were implanted 3 days after SE. After one-hour
recovery cortical epileptic afterdischarges (ADs) were elicited by 15-s series of lowfrequency (8 Hz) pulses. Intensity was increased stepwise from 0.2 to 15 mA, interval
between stimulation series was at least 10 minutes. Threshold intensities for
movements during stimulation, spike-and-wave ADs, clonic seizures, transition to limbic
(mixed) ADs and recurrent ADs as well as durations of spike-and-wave (SW) and mixed
ADs were measured.
Results
Only threshold intensities for movements were increased 3 days after SE,
thresholds for other measured phenomena remained untouched. Mixed type of seizures
and recurrent ADs failed to appear after SE at this interval. Administration of either LiCl
or paraldehyde as well as their combination also led to an increase of threshold for
movements. Changes in duration of Spike-and-Wave ADs caused by LiCl are prone to
those in SE group.
Conclusions
Administration of LiCl or/and paraldehyde plays a role in short-time effect of
SE on cortical excitability but they do not influence elicitation of mixed and recurrent
afterdischarges.
This study was supported by a grant No. 305/05/2582 and by a research project AV0Z
50110509.
106
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Software for synchronous electrophysiologic and
image recordings and high level mathematical
analysis
E. KRAJČOVIČOVÁ*, M. MARTINKOVÁ*, R. KONOPKOVÁ, M. FEJTOVÁ, J. OTÁHAL
* these authors contributed equally on present work
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague
Department of cybernetics, Czech Technical University in Prague
In present, in neuroscience is increasingly important to combine synchronous
optical and electric signals detection and analysis. However, majority systems
reachable on the market are tools specialized for either imaging or electrophysiology not
combining both in one environment. Moreover, high level mathemathical analysis is
currently done separately usually in home based scripts written in Matlab. The aim of
present study was to develope free software for broadly used windows based computer
systems with low cost NI data acquisition cards series M and standard set of
videocameras which will provide simple user interface for both types of recordings,
triggering external devices like stimulator and powerfull matlab interoperability.
The software was programmed using Microsoft .NET Framework 2.0 library
and C# programming language and thus it is suitable for any MS Windows based
computer. For digitalization of voltage signals M series PCI data acquisition boards
(National Instruments) were chosen for their high temporal and bit resolution. The
communication with the card is done using low level NI-DAQmx driver programming
allowing optimalization of hardware tasks. For image acquisition we have developed
software components which make possible to acquire from standard webcams, DV
cams and selected high sensitive cameras for microscopy use (UI, Q-Imaging, etc.).
Communication with matlab is based on two different approaches. The first is based on
compilling user matlab scripts into .NET dll libraries using Matlab .NET builder to
calculate partial results for later processing or display in the software, the second
approach is based on communication with COM Automation server object of Matlab
which allows transferring of data to Matlab for further processing or displaying in its own
environment.
The software was tested with PCI-6221 (National Instruments, Czech
Republic) data acquisition board (16bit, 250kS/s, 16 AI and 2AO channels) with
homemade EEG four channel amplifiers for signal preconditioning. For video recording
we have tested simultaneous image acquisition with high resolution webcam (Philips
900NC), industrial cameras UI-2230C and 2230M (ids imaging, Germany) and high
sensitive cooled camera Retiga 2000R (Q-imaging).
The project was supported by grant of the Academy of Sciences of the Czech Republic
number 1QS501210509.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
107
Effect of methamphetamine exposure and postnatal
care on sensorimotor development of rat pups
L. HRUBÁ, B. SCHUTOVÁ, M. POMETLOVÁ, R. ŠLAMBEROVÁ
Charles University in Prague, Third Faculty of Medicine, Department of Normal,
Pathological and Clinical Physiology, Prague, Czech republic
Our previous studies demonstrated that methamphetamine (MA) administered
during gestation and lactation periods impairs maternal behavior as well as the
postnatal development of rat pups. The present study tested the hypothesis that the
postnatal care of adoptive mother influences the development of rat pups. The aim of
our study was to distinguish the extent of the drug-induced effect and the extent of the
effect induced by impaired maternal care. Mothers were daily exposed to injection of
MA (5 mg/kg) or saline (S) approximately for 9 weeks: about three weeks prior to
impregnation, throughout the entire gestation period and during lactation until the
weaning period. As an absolute control (C) females with no injections were used. On
postnatal day (PD 1), pups were cross-fostered so that each mother received some of
her own and some of the pups of mother with the other two treatments. Based on the
prenatal and postnatal treatments 9 experimental groups (CC, CS, CM, SC, SS, SM,
MC, MS, MM) were tested. Pup’s development and sensorimotor coordination was
examined between PD 1 and PD 23. Following behavioral tests were used: negative
geotaxis (PD 9 and 11), tail pull on cellulose cotton wool and on grid (PD 10, 12 and
14), righting reflex on surface (PD 12), righting reflex on mid-air (PD 17), rotarod (PD
23) and bar-holding (PD 23). Further, the pups were examined for physiological
maturation (weight gain during lactation, startle response, tooth eruption and ear and
eye opening). Our results showed that the birth weight in prenatally MA-exposed pups
was lower than controls or saline-exposed pups regardless of sex. Prenatally MAexposed pups gained less weight than controls or saline-exposed pups regardless of
postnatal treatment and sex. On the other hand, prenatally MA-exposed pups fostered
by control or saline-exposed dams gained more weight during lactation. MA-exposed
pups regardless of postnatal drug exposure and sex had displayed startle response, ear
and eye opening later than control or saline-exposed pups. Further, our data
demonstrated that pre- and postnatal MA exposure impairs sensorimotor functions in
these tests: negative geotaxis, tail pull, righting reflex on surface, righting reflex in midair and rotarod. On the other hand, postnatal care of control mothers at least partially
suppressed the negative effect of prenatal MA exposure. Our hypothesis, that the care
of adoptive mother may affect postnatal development of pups, was confirmed.
Supported by: CN LC554, IGA 1A8610/5-2005 and MSM 0021620816
108
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Effect of methamphetamine on social and locomotion
behaviors of adult male rats
B. SCHUTOVÁ, L. HRUBÁ, M. POMETLOVÁ, K. DEYKUN, R. ŠLAMBEROVÁ
Third Faculty of Medicine, Charles University in Prague, Department of Normal,
Pathological and Clinical Physiology, Prague, Czech Republic
Psychostimulants have been shown to affect human behavior in serious
manner; specifically they induce aggressive behaviors and impair social interaction.
Increased anxiety caused by psychostimulants was found in several types of tests. The
aim of the present study was to assess the effect of low dose of methamphetamine
(MA) on social interaction and locomotion in adult male rats. Test of social interaction
(SIT) was used as a test of anxiety. SIT was tested in three different levels of stressful
conditions: low stress, middle stress, high stress, depending on lighting intensity and
known/unknown arena. Rats were or were not, respectively, habituated in an open field
arena for 10 minutes on 2 consecutive days. Thirty minutes prior to SIT half of the
animals were injected subcutaneously (s.c.) with MA (1.0 mg/kg). The other half of the
animals did not receive any drugs. Social interaction (SI) was tested in the open field for
five minutes and recorded by using a video camcorder. Animals of the same treatment
and weight were assigned to one pair. Each pair was assessed as a unit and time spent
by social interaction and locomotion was recorded and analyzed using a One-way
ANOVA (drug treatment) for each condition separately. Locomotion (swimming activity)
was further tested in the Morris water maze (MWM). The tests consisted of eight trials a
day and lasted for five days. The same dose of MA (1 mg/kg) was given to half of the
rats after finishing all 8 trials each day. The other half were not administered any drugs
and were assigned to be a control group. A One-way ANOVA (drug treatment) was
used for data analysing. Our results showed that acute MA administration decreased SI
while increasing locomotion in the open field test relative to controls. This effect of MA
depended on the level of stressful condition. Further, acute MA administration increased
the speed of swimming in individual trials. Thus, our study indicates that application of
MA at low doses decreases SI, thereby has anxiogenic effect, and increases locomotor
activities tested in both Open field and MWM tests.
Supported by: CN LC554, GACR 305/06/0283 and MSM 0021620816
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
109
Effect of acute methamphetamine administration on
seizures in adult male and female rats prenatally
exposed to the same drug
R. ŠLAMBEROVÁ, B. SCHUTOVÁ, L. HRUBÁ, K. BERNÁŠKOVÁ, I. MATĚJOVSKÁ,
R. ROKYTA
Charles University in Prague, Third Faculty of Medicine, Department of Normal,
Pathological and Clinical Physiology, Prague, Czech Republic
The aim of the present study was to investigate whether sensitivity to seizures
after acute methamphetamine (MA) administration (5mg/kg) is different in prenatally
MA-exposed adult rats compared to controls without prenatal drug exposure. Adult rats
with respect to sex and female estrous cycle (prenatally MA-exposed, prenatally salineexposed and controls) were divided into groups with or without acute MA (1mg/kg)
administration. Two models of seizures were used. Seizures induced by inhalation of
flurothyl, gas that is assumed to inhibit GABAA receptors; and seizures induced by
injection of 250 mg/kg of N-Methyl-D-Aspartate (NMDA), agonist of NMDA receptors. In
flurothyl-induced seizures: prenatal MA exposure decreased threshold of the first clonus
relative to prenatally saline-exposed and control animals. Acute MA administration
increased threshold to the first clonus and clonic seizures and shortened duration of
clonic seizures regardless of prenatal drug exposure. Prenatally saline-exposed animals
with acute MA administration decreased threshold in all measures (first clonus, clonic
seizures and tonic-clonic seizures) relative to prenatally MA-exposed and control rats
with acute MA injection. In NMDA-induced seizures, acute MA administration increased
latency to onset of stereotypic behavior in control and prenatally MA-exposed rats, while
decreased latency to onset of clonic-tonic seizures in prenatally saline-exposed rats.
The length of clonic-tonic seizures induced by NMDA was longer after acute MA
pretreatment relative to animals without acute MA injection in all experimental groups. In
both models, there were sex and/or estrous cycle-induced differences. Our study
suggests that acute MA exposure changes seizure susceptibility in respect of prenatal
drug exposure and hormonal status in two models of epileptic seizures.
Supported by: CN LC554, CNS 1M0517 and MSM 0021620816.
110
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Analgesic effect of acute methamphetamine in
prenatally stressed and methamphetamine-treated
rats
A. YAMAMOTOVÁ, R. ŠLAMBEROVÁ, R. ROKYTA
Charles University in Prague, Third Faculty of Medicine, Department of Normal,
Pathological and Clinical Physiology, Prague, Czech Republic
Recently we have shown that prenatal methamphetamine (METH), stress,
and fostering affect differently nociception in adult animals (1). As METH possesses an
analgesic effect, we decided to test its acute effect in adult animals with prenatal
experience with the same drug.
Methods: Nociception was tested during the 85-90 postnatal day in three groups of
Wistar male rats (N=27). Two groups consisted of animals, whose mothers were during
gestation and lactation daily treated with METH (5mg/kg; s.c.) or saline (STRESS). The
control group consisted of intact animals without any prenatal and postnatal
intervention. Latencies of withdrawal reflexes of forelimbs, hind limbs and the tail on
thermal nociceptive stimuli (Plantar Test, Ugo Basile, Comero, Italy) were repeatedly
measured in 15-min intervals after the application of 1mg/kg s.c. of METH. Last
measurement was performed 75 min after the injection.
Results: There were no group differences either in baseline nociception or in absolute
level of METH-induced analgesia. In all groups, analgesia increased in cranio-caudal
direction, with the smallest values observed in forelimbs (124% of the baseline values)
and the highest values observed in the tail (249% of the baseline values). Analgesia in
the METH group was already present 15 min after the injection. The slowest progress of
analgesia occurred in the control group and it was dependent on measured site; it took
30 min for hind limbs and the tail and 60 min for forelimbs. In forelimbs of STRESS
group, METH had a biphasic effect with hyperalgesia followed by mild analgesia.
Discussion: METH is a stimulatory drug which increases brain dopamine, serotonin
and noradrenalin levels. All these neurotransmitters are important modulators in
descendent antinociceptive system. As the main group differences were observed in the
speed of analgesic process instead of its absolute values, we suppose that prenatal
exposition to METH may have sensitization effect especially on dopaminergic brain
reward system, which also can represent a common-final pathway of both opioid and
non-opioid analgesia. Thus, our results show that the long-term consequences may be
induced even by prenatal exposition to the drug.
(1) Yamamotová A, Šlamberová R, Fifth Conference of the Czech Neuroscience
Society, Prague November 19-21, 2005, p.146.
Supported by grants GACR 305/03/0774, CN LC 554, and CNS 1M0517.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
111
Grooming induced by intraperitoneal application of
malanotan II, a dirivative of α-MSH
S. HYNIE, M. FLEGEL, V. KLENEROVÁ
Laboratory of Biochemical Neuropharmacology, Institute of Medical Biochemistry, 1st
Faculty of Medicine, Charles University in Prague, Albertov 4, Prague 2, Czech
Republic
Melanocortin II (MTII) is a cyclic peptide analog of αMSH; it acts on MC4
receptor subtype, which is believed to participate on stress responses and stressinduced behaviors (1,2,3). In rodents MTII-stimulated receptors cause the grooming.
We investigated the involvement of MTII on stress-induced behaviors, such as activity,
exploration and anxiety, in order to find whether i.p. application of this peptide will
influence these parameters. Further, we were interested whether MTII will influence
grooming and whether it will be changed at the simultaneous action of restraint stress.
Male Wistar rats (Velaz, Czech Republic) (290-305g) were used. Rats were exposed to
60 min immobilization (IMO) (4,5). MTII (2mg/kg b.w.) given i.p. immediately after
stress termination; testing in the open-field was performed one hour later. Behavior of
rats was video-monitored by an activity monito-ring system (AnyMaze, Stoelting, USA)
in a circular arena with the diameter of 150 cm.
We have demonstrated in the open-field test that a derivative of αMSH MTII
stimulated grooming and strongly increased grooming induced by immobilization stress.
Other behavio-ral parameters, namely activity (locomotion), exploration (rearing) and
anxiety (entry into the inner zone of the device) were not substantially influenced. The
results support the notion that melanocortins influence some of the behavioral outcomes
of stress, supposedly by acting on MC4 receptors. Under the used experimental
conditions MTII selectively increased grooming without affecting the spatio-temporal
structure of locomotor behavior in the open field.
References:
1. R.A.H. Adan, A.W. Szklarczyk, J. Oosterom et al. Characterization of melanocortin receptor
ligands cloned brain melanocortin receptors and on grooming behavior in the rat. Europ. J.
Pharmacol. 378 (1999) 249-258;
2. S. Chaki, S. Ogawa, Y. Toda, T. Funakoshi, T. S. Okuyama. Involvement of the melanocortin
MC4 receptor in stress-related behavior in rodents. Europ. J. Pharmacol. 474 (2003) 95-101.
3. D. Colbern, R.L. Isaacson, J.H. Hannigan, Water immersion, excessive grooming, and paper
shredding in the rat. Behavioral and Neural Biology 32 (1981) 428-432.
4. V. Klenerová, I. Krejčí, P. Šída, Z. Hliňák, S. Hynie, Timing of stress and testing influence the
long-lasting behavioural performance in rats. Neurosci. Letters 410 (2006) 100-104.
5. V. Klenerová, P. Šída, I. Krejčí, Z. Hliňák, S. Hynie, Effects of two types of restraint stress on
spontaneous behavior of Sprague-Dawley and Lewis rats. J. Physiol. Pharmacol. 58 (2007) 83-94.
Supported by grants MSM 0021620806 and GACR 309/06/0,121.
112
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Carbetocin improves deterioration of stress-induced
behavior in the open-field device
V. KLENEROVÁ, M. FLEGEL, P. ŠÍDA, S. HYNIE
Laboratory of Biochemical Neuropharmacology, Institute of Medical Biochemistry,1st
Faculty of Medicine, Charles University in Prague, Albertov 4, Prague 2, Czech
Republic
Carbetocin (1-butanoic acid-2-/O-methyl-Ltyrosine/1-carbaoxytocin) is a longacting analogue of a neurohypophyseal nonapeptide hormone oxytocin that is used to
control postpartum bleeding and is also indicated for the treatment and prevention of
breast cancer and psychiatric disorders like autism and obsessive-compulsive disorder.
There are only very limited data on the central effects of carbetocin after its application
peripherally.
The aim of this study was to compare the effects of oxytocin and carbetocin
on Wistar rat´s behavior in the open-field device after administration of
restraint/immobilization stress (IMO), which is known to change basic behavioral
parameters in the open-field test (1,2). We used male Wistar rats (Velaz, Czech
Republic), and IMO was applied for 60 min. Saline, oxytocin or carbetocin (0,3 or 1,0
mg/kg b.w.) were administered i.p. immediately after stress termination. After 60 min
lasting pause the tests were performed in the large (150 cm diameter) circular arena
and behavior was recorded by AnyMaze software (Stoelting Co, USA).
When compared to controls IMO alone reduced locomotion as well as
exploratory activity and revealed increased sings of anxiety. Oxytocin applied after IMO
slightly decreased behavioral parameters when compared to IMO alone. Carbetocin (1
mg/kg) antagonized the behavioral parameters induced by IMO and returned them
nearly to control values. Lower dose of drugs produced similar changes, however no
sedative effect of oxytocin was observed. The experiment with higher dose was
repeated three times in three consecutive days and the effect of carbetocin was
strongest on the third day. In summary, carbetocin was shown to have strong
antagonistic effect on behavioral manifestations of stress; we speculate that this drug
can be used for treatment of some stress-induced effects.
References:
1. V. Klenerová, I. Krejčí, P. Šída, Z. Hliňák, S. Hynie, Timing of stress and testing
influen-ce the long-lasting behavioural performance in rats. Neurosci. Letters 410 (2006)
100-104.
2. V. Klenerová, P. Šída, I. Krejčí, Z. Hliňák, S. Hynie, Effects of two types of restraint
stress on spontaneous behavior of Sprague-Dawley and Lewis rats. J. Physiol.
Pharmacol. 58 (2007) 83-94
Supported by grants MSM 0021620806 and GACR 309/06/0121.
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
Author index
A
D
AMEMORI, T. · 52
ANDĚROVÁ, M. · 46, 47, 48, 49, 50,
60
ARBOLEDA TORO, G.D. · 52
DEYKUN, K. · 101, 108
DITTERT, I. · 20
DLOUHÁ, O. · 70
DMYTRENKO, L. · 59
DOLEŽAL, V. · 29, 89, 90
DRUGA, R. · 34, 63, 65, 99
DUBOVÝ, P. · 25, 44
DURCHÁNKOVA, D. · 88
DVOŘÁK, M. · 91
B
BALÍK, A. · 85
BARCAL, J. · 98
BAŘINKA, F. · 99
BĚLÁČEK, J. · 24
BENEDIKT, J. · 37, 39
BENEŠOVÁ, J. · 48, 49
BERNÁŠKOVÁ, K. · 109
BLAHNA, K. · 73, 75
BOJAR, M. · 32, 80
BORBELY, S. · 102
BOUŘA, E. · 81, 82
BOUŘOVÁ, L. · 28, 87
BUCKIOVÁ, D. · 61
BUREŠ, J. · 76
BURIAN, M. · 57
BURIANOVÁ, J. · 62
BUTENKO, O. · 48, 49, 50
E
EL-FAKAHANY, E.E. · 89, 90
F
FAJNEROVÁ, I. · 74
FEJTOVÁ, M. · 106
FLEGEL, M. · 111, 112
FRANĚK, M. · 43
FRIEDLOVÁ, E. · 83, 84
G
C
CAIS, O. · 20
CENDELÍN, J. · 79
CIHELKOVÁ, Š. · 80
CLARKE, S. · 21
CRESPO, J.A. · 18
Č
ČERNÝ, R. · 32
GRÉCOVÁ, J. · 67
GROH, D. · 68
GRYCOVÁ, L. · 83, 84
H
HÁJEK, M. · 60
HAMPL, A. · 50
HAMSOVÁ, S. · 64
HEJČL, A. · 54, 57
HEJNOVA, L. · 87
HERMAN, P. · 82
HLADÍKOVÁ, M. · 80
113
114
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
HOCK, M. · 48
HOMOLA, A. · 58
HONSA, P. · 46, 47
HORÁK, M. · 20
HORT, J. · 78
HOŘÍNEK, A. · 97
HOVORKOVÁ, P. · 97
HOZMAN, J. · 32
HRUBÁ, L. · 107, 108, 109
HUT, R. · 93
HYNIE, S. · 111, 112
Ch
CHODOUNSKÁ, H. · 38
CHVÁTAL, A. · 46, 47, 48, 49
I
KLENEROVÁ, V. · 111, 112
KLUČKOVÁ, K. · 28
KLUSÁKOVÁ, I. · 25, 44
KONOPKOVÁ, R. · 106
KONOPKOVÁ, R. · 102
KORELUSOVÁ, I. · 79
KOŠŤÁL, L. · 71
KOZMÍKOVÁ, I. · 94
KOZUBENKO, N. · 50
KRAJČOVIČOVÁ, E. · 106
KREMLÁČEK, J. · 23
KRIŠTOFÍKOVÁ, Z. · 97
KRŠEK, P. · 58
KRUŠEK, J. · 88
KRŮŠEK, J. · 40
KRÝSL, D. · 100
KUBA, M. · 23
KUBALA, M. · 84
KUBOVÁ, H. · 33, 34, 103, 105
KUBOVÁ, H. · 102
KUBOVÁ, Z. · 23
KUNEŠ, J. · 57
ILLNEROVÁ, H. · 93
L
J
JAKUBÍK, J. · 29, 89
JANČÁLEK, R. · 25
JECH, R. · 31
JELÍNKOVÁ, I. · 86
JENDELOVÁ, P. · 50, 51, 52, 53, 54,
55, 56, 57
JILEK, M. · 68, 69
JINDŘICHOVÁ, M. · 86
JINOCH, P. · 80
JIRÁK, D. · 60
JIROUTEK, P. · 45
JIRSÁK, O. · 56
K
KABELKA, Z. · 68
KAPCALOVÁ, M. · 50, 55
KENNEY, J. · 74
KLASCHKA, J. · 94, 95, 96
KLEMENT, D. · 73, 74, 75
LACZO, J. · 78
LANGROVÁ, J. · 23
LÁNSKÝ, P. · 71, 72
LÁNSKÝ, Z. · 83, 84
LESNÝ, P. · 54, 55, 56
LIKAVČANOVÁ, K. · 53, 57
LISÝ, V. · 28
LOMAKINA, K. · 66
M
MACHON, O. · 46
MACHOVÁ, E. · 89
MAJER, E. · 97
MALOMOUZH, AI · 92
MAŇÁSKOVÁ, V. · 73
MAREŠ, J. · 100, 101
MAREŠ, P. · 34, 35, 104, 105
MARTINKOVÁ, M. · 106
MARTINOVÁ, L. · 55, 56
MARUSIČ, P. · 58
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
MATĚJOVSKÁ, I. · 109
MATĚJŮ, K. · 93
MICHAL, P. · 90
MICHÁLEK, J. · 54, 56
MIKULECKÁ, A. · 104
MINÁRIKOVÁ, M. · 80
MRÁZOVÁ, P. · 103
MUKHTAROV, MR · 92
ROKYTA, R. · 43, 109, 110
ROSPARS, JEAN-PIERRE · 71
RUDAJEV, V. · 28
RŮŽIČKOVÁ, K. · 51, 52
RYBALKO, N. · 64
Ř
N
ŘÍČNÝ, J. · 97
ŘÍPOVÁ, D. · 97
NEPRAŠOVÁ, H. · 49, 60
NIKOLSKY, EE · 92
NOVOTNÝ, J. · 28, 87, 88
S
O
OBŠIL, T. · 27, 81, 82, 86
OGDEN, D. · 19
ORT, M. · 78
OSECKÁ, B. · 73
OSTAŠOV, P. · 87, 88
OTÁHAL, J. · 102, 103, 106
OUDA, L. · 62, 63
P
PALEČEK, J. · 26, 41, 42
PELÁNOVÁ, J. · 64, 68
PETROVIČ, M. · 38
POKORA, O. · 72
POKORNÝ, J. · 100
POMETLOVÁ, M. · 101, 107, 108
POPELÁŘ, J. · 67
POSPÍŠILOVÁ, E. · 26
PRAJEROVÁ, I. · 46, 47, 48
PROFANT, O. · 62, 66
PROŠKA, J. · 91
PŘÁDNÝ, M. · 54, 56
R
ROCHA, L. · 33
115
SAMAD, A. · 37, 39
SARIA, A. · 18
SEDLÁČEK, M. · 20, 38
SCHUTOVÁ, B. · 107, 108, 109
SLÁDEK, M. · 93
SOJKA, D. · 42
SOSNIYENKO, S. · 93
STARÝ, J. · 68
STOHR, J. · 28
STOJILKOVIC, S.S. · 27, 86
STUCHLÍK, A. · 77
STURM, K. · 18
SUCHOMELOVÁ, L. · 33
SUMERAUER, D. · 68
SUMOVÁ, A. · 93
SUŠÁNKOVÁ, K. · 37, 40
SVÍŽENSKÁ, I. · 25, 44
SVOBODA, J. · 76
SVOBODA, P. · 28, 87, 88
SVOBODOVÁ, I. · 85
SYKA, J. · 22, 61, 62, 63, 64, 65, 66,
67, 68, 69
SYKOVÁ, E. · 17, 50, 51, 52, 53, 54,
55, 56, 57, 58, 59, 60
SZANYI, J. · 23
Š
ŠEDÝ, J. · 53, 54, 57
ŠEFC, L. · 45
ŠÍDA, P. · 112
ŠILHAN, J. · 82
116
6TH CONFERENCE OF THE CZECH NEUROSCIENCE SOCIETY, PRAGUE, 2007
ŠKODA, D. · 80
ŠLAIS, K. · 59
ŠLAMBEROVÁ, R. · 107, 108, 109,
110
ŠPICAROVÁ, D. · 26, 41
ŠŤASTNÝ, F. · 94, 95, 96
ŠTURM, D. · 32
ŠULC, M. · 83
ŠUTA, D. · 64
T
TABASHIDZE, N. · 35
TEISINGER, J. · 37, 39, 83, 84
TEJKALOVÁ, H. · 94, 95, 96
TELENSKÝ, P. · 76
TICHÝ, J. · 24, 70
TOMIC, M. · 27
TOUŠKA, F. · 40
TOUŠOVÁ, K. · 37
TSENOV, G. · 103, 105
TŮMA, L. · 100
TUREČEK, R. · 66
TURNOVCOVÁ, K. · 51
VÁVRA, V. · 86
VEČER, J. · 82
VESELKOVÁ, Z. · 44
VILAGI, I. · 102
VÍT, F. · 23
VITÁK, T. · 70
VLACHOVÁ, V. · 37, 39, 40
VLČEK, K. · 78
VOŘÍŠEK, I. · 59, 60
VOŽEH, F. · 79, 98
VRAJOVÁ, M. · 94, 96
VRBA, J. · 98
VYHNÁLEK, M. · 78
VYKLICKÝ JR., L. · 20, 38
VYKLICKÝ, L. · 37, 39
VYMAZAL, J. · 31
VYSKOČIL, F. · 30, 92
Y
YAMAMOTOVÁ, A. · 110
YAN, Z. · 27
Z
U
URDZIKOVÁ, L. · 53, 57
V
VACULÍN, S. · 43
VÁCHA, P. · 82
VAJNEROVÁ, O. · 78
VALEŠ, K. · 77
VARGOVÁ, L. · 58
ZÁMEČNÍK, J. · 58, 99
ZÁPOTOCKÝ, M. · 68
ZEMKOVÁ, H. · 27, 85, 86
ZEMKOVÁ, H.W. · 86
ZERNIG, G. · 18
ZICHA, J. · 57
Ž
ŽALUD, V. · 98
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